chore(release): update package version to 1.0.74

* Add handling for pgvector and PostGIS extensions in migration scripts
* Implement operator class and storage parameters for vector indexes
* Update tests to validate new index behaviors and extension creation

linux/arch/PKGBUILD

@@ -1,6 +1,6 @@
 # Maintainer: Hein (Warky Devs) <hein@warky.dev>
 pkgname=relspec
-pkgver=1.0.73
+pkgver=1.0.74
 pkgrel=1
 pkgdesc="RelSpec is a comprehensive database relations management tool that reads, transforms, and writes database table specifications across multiple formats and ORMs."
 arch=('x86_64' 'aarch64')

linux/centos/relspec.spec

@@ -1,5 +1,5 @@
 Name:           relspec
-Version:        1.0.73
+Version:        1.0.74
 Release:        1%{?dist}
 Summary:        RelSpec is a comprehensive database relations management tool that reads, transforms, and writes database table specifications across multiple formats and ORMs.
 

pkg/pgsql/extensions.go

@@ -0,0 +1,459 @@
+package pgsql
+
+import (
+	"sort"
+	"strings"
+)
+
+// Extension describes a PostgreSQL extension RelSpec recognizes, along with the schema
+// artefacts that imply it: the types it provides (declared on TypeSpec.Extension), the
+// index access methods and operator classes it installs, and the functions whose use in a
+// default, check constraint, index predicate, or view body requires it.
+type Extension struct {
+	Name        string
+	Category    string
+	Description string
+
+	// Requires lists extensions that must be created before this one.
+	Requires []string
+
+	// IndexMethods are access methods usable as Index.Type.
+	IndexMethods []string
+
+	// OperatorClasses are operator classes the extension installs.
+	OperatorClasses []string
+
+	// Functions are function names whose use implies the extension.
+	Functions []string
+
+	// FunctionPrefixes match whole families of functions (e.g. "st_" for PostGIS).
+	FunctionPrefixes []string
+}
+
+// postgresExtensions is the set of extensions RelSpec knows how to detect and emit.
+var postgresExtensions = map[string]Extension{
+	"amcheck": {
+		Name: "amcheck", Category: "integrity",
+		Description: "Verifies B-tree and related structure consistency to help detect corruption.",
+		Functions:   []string{"bt_index_check", "bt_index_parent_check", "verify_heapam"},
+	},
+	"btree_gin": {
+		Name: "btree_gin", Category: "indexing",
+		Description: "Adds GIN operator classes for common scalar data types.",
+	},
+	"btree_gist": {
+		Name: "btree_gist", Category: "indexing",
+		Description: "Adds GiST operator classes for common scalar data types and exclusion constraints.",
+	},
+	"citext": {
+		Name: "citext", Category: "text",
+		Description: "Provides case-insensitive text columns and operators.",
+		Functions:   []string{"citext"},
+	},
+	"fuzzystrmatch": {
+		Name: "fuzzystrmatch", Category: "text",
+		Description: "Adds phonetic and fuzzy matching helpers like Soundex and Levenshtein.",
+		Functions: []string{
+			"soundex", "difference", "levenshtein", "levenshtein_less_equal",
+			"metaphone", "dmetaphone", "dmetaphone_alt",
+		},
+	},
+	"hstore": {
+		Name: "hstore", Category: "document",
+		Description:     "Adds a lightweight key/value data type for semi-structured attributes.",
+		OperatorClasses: []string{"gin_hstore_ops", "gist_hstore_ops", "hash_hstore_ops", "btree_hstore_ops"},
+		Functions: []string{
+			"hstore", "akeys", "avals", "skeys", "svals",
+			"hstore_to_json", "hstore_to_jsonb", "hstore_to_array", "hstore_to_matrix",
+		},
+	},
+	"http": {
+		Name: "http", Category: "integration",
+		Description: "Lets SQL functions make outbound HTTP requests.",
+		Functions: []string{
+			"http", "http_get", "http_post", "http_put", "http_patch", "http_delete",
+			"http_head", "urlencode",
+		},
+	},
+	"pg_background": {
+		Name: "pg_background", Category: "jobs",
+		Description: "Runs SQL asynchronously in PostgreSQL background workers.",
+		Functions:   []string{"pg_background_launch", "pg_background_result", "pg_background_detach"},
+	},
+	"pg_cron": {
+		Name: "pg_cron", Category: "scheduling",
+		Description:      "Schedules recurring SQL jobs inside PostgreSQL.",
+		FunctionPrefixes: []string{"cron."},
+	},
+	"pg_jsonschema": {
+		Name: "pg_jsonschema", Category: "validation",
+		Description: "Validates json and jsonb values against JSON Schema.",
+		Functions:   []string{"json_matches_schema", "jsonb_matches_schema", "jsonschema_is_valid"},
+	},
+	"pg_partman": {
+		Name: "pg_partman", Category: "partitioning",
+		Description:      "Automates time-based and serial-based partition management.",
+		FunctionPrefixes: []string{"partman."},
+	},
+	"pg_qualstats": {
+		Name: "pg_qualstats", Category: "observability",
+		Description: "Tracks predicate usage in WHERE and JOIN clauses for tuning and index advice.",
+	},
+	"pg_repack": {
+		Name: "pg_repack", Category: "maintenance",
+		Description: "Rebuilds bloated tables and indexes online with minimal locking.",
+	},
+	"pg_search": {
+		Name: "pg_search", Category: "search",
+		Description: "Provides ParadeDB full-text and relevance search features.",
+		// bm25 is also the access method name used by pg_textsearch; pg_search is the
+		// canonical provider, so a bm25 index resolves to it.
+		IndexMethods:     []string{"bm25"},
+		FunctionPrefixes: []string{"paradedb."},
+	},
+	"pg_stat_statements": {
+		Name: "pg_stat_statements", Category: "observability",
+		Description: "Tracks normalized query execution statistics.",
+	},
+	"pg_textsearch": {
+		Name: "pg_textsearch", Category: "search",
+		Description: "Adds BM25-style text search support.",
+	},
+	"pg_trgm": {
+		Name: "pg_trgm", Category: "text",
+		Description:     "Adds trigram similarity search and fast fuzzy matching indexes.",
+		OperatorClasses: []string{"gin_trgm_ops", "gist_trgm_ops"},
+		Functions: []string{
+			"similarity", "word_similarity", "strict_word_similarity",
+			"show_trgm", "show_limit", "set_limit",
+		},
+	},
+	"pgcrypto": {
+		Name: "pgcrypto", Category: "security",
+		Description: "Adds hashing, encryption, random bytes, and UUID helpers.",
+		// gen_random_uuid is deliberately absent: it is built in since PostgreSQL 13.
+		Functions: []string{
+			"crypt", "gen_salt", "gen_random_bytes", "digest", "hmac",
+			"pgp_sym_encrypt", "pgp_sym_decrypt", "pgp_pub_encrypt", "pgp_pub_decrypt",
+			"armor", "dearmor",
+		},
+	},
+	"pgrouting": {
+		Name: "pgrouting", Category: "geospatial",
+		Description:      "Adds routing and graph algorithms on top of PostGIS data.",
+		Requires:         []string{"postgis"},
+		FunctionPrefixes: []string{"pgr_"},
+	},
+	"pgstattuple": {
+		Name: "pgstattuple", Category: "maintenance",
+		Description: "Reports table and index tuple density and bloat information.",
+		Functions:   []string{"pgstattuple", "pgstatindex", "pgstatginindex", "pg_relpages"},
+	},
+	"plpython3u": {
+		Name: "plpython3u", Category: "procedural",
+		Description: "Lets you write PostgreSQL functions in Python 3.",
+	},
+	"postgis": {
+		Name: "postgis", Category: "geospatial",
+		Description:  "Adds spatial data types, functions, and indexes.",
+		IndexMethods: nil, // uses the built-in gist/spgist/brin access methods
+		OperatorClasses: []string{
+			"gist_geometry_ops_2d", "gist_geometry_ops_nd", "gist_geography_ops",
+			"spgist_geometry_ops_2d", "spgist_geometry_ops_3d", "spgist_geometry_ops_nd",
+			"brin_geometry_inclusion_ops_2d", "brin_geometry_inclusion_ops_3d",
+			"brin_geometry_inclusion_ops_4d", "brin_geography_inclusion_ops_2d",
+			"btree_geometry_ops", "btree_geography_ops",
+		},
+		FunctionPrefixes: []string{"st_"},
+		Functions: []string{
+			"geometrytype", "addgeometrycolumn", "dropgeometrycolumn", "updategeometrysrid",
+			"find_srid", "postgis_version", "postgis_full_version",
+		},
+	},
+	"postgis_raster": {
+		Name: "postgis_raster", Category: "geospatial",
+		Description: "Adds the raster type and raster analysis functions.",
+		Requires:    []string{"postgis"},
+	},
+	"postgis_topology": {
+		Name: "postgis_topology", Category: "geospatial",
+		Description:      "Adds topology-aware spatial models and validation tools.",
+		Requires:         []string{"postgis"},
+		FunctionPrefixes: []string{"topology."},
+	},
+	"postgres_fdw": {
+		Name: "postgres_fdw", Category: "federation",
+		Description: "Connects PostgreSQL tables to other PostgreSQL servers.",
+	},
+	"timescaledb": {
+		Name: "timescaledb", Category: "time-series",
+		Description: "Adds hypertables, compression, retention, and time-series optimizations.",
+		Functions: []string{
+			"create_hypertable", "add_dimension", "time_bucket", "time_bucket_gapfill",
+			"add_retention_policy", "add_compression_policy", "locf", "interpolate",
+		},
+	},
+	"unaccent": {
+		Name: "unaccent", Category: "text",
+		Description: "Removes accents and diacritics for normalized text search.",
+		Functions:   []string{"unaccent"},
+	},
+	"uuid-ossp": {
+		Name: "uuid-ossp", Category: "utility",
+		Description: "Generates UUIDs using several algorithms.",
+		Functions: []string{
+			"uuid_generate_v1", "uuid_generate_v1mc", "uuid_generate_v3",
+			"uuid_generate_v4", "uuid_generate_v5",
+			"uuid_nil", "uuid_ns_dns", "uuid_ns_url", "uuid_ns_oid", "uuid_ns_x500",
+		},
+	},
+	"vector": {
+		Name: "vector", Category: "ai/search",
+		Description:  "Adds vector data types and similarity search for embeddings.",
+		IndexMethods: []string{"hnsw", "ivfflat"},
+		OperatorClasses: []string{
+			"vector_l2_ops", "vector_ip_ops", "vector_cosine_ops", "vector_l1_ops",
+			"halfvec_l2_ops", "halfvec_ip_ops", "halfvec_cosine_ops", "halfvec_l1_ops",
+			"sparsevec_l2_ops", "sparsevec_ip_ops", "sparsevec_cosine_ops", "sparsevec_l1_ops",
+			"bit_hamming_ops", "bit_jaccard_ops",
+		},
+		Functions: []string{"l2_distance", "inner_product", "cosine_distance", "l1_distance", "vector_dims", "vector_norm"},
+	},
+	"vchord": {
+		Name: "vchord", Category: "ai/search",
+		Description:  "Adds VectorChord scalable disk-friendly vector indexes compatible with pgvector data types.",
+		Requires:     []string{"vector"},
+		IndexMethods: []string{"vchordrq", "vchordg"},
+	},
+	"ltree": {
+		Name: "ltree", Category: "document",
+		Description:     "Adds a hierarchical label tree type.",
+		OperatorClasses: []string{"gist_ltree_ops", "gin_ltree_ops", "gist__ltree_ops"},
+		Functions:       []string{"subltree", "subpath", "nlevel", "lca", "ltree2text", "text2ltree"},
+	},
+}
+
+// extensionIndexMethods maps an index access method to the extension providing it.
+var extensionIndexMethods = buildExtensionIndex(func(ext Extension) []string { return ext.IndexMethods })
+
+// extensionOperatorClasses maps an operator class to the extension providing it.
+var extensionOperatorClasses = buildExtensionIndex(func(ext Extension) []string { return ext.OperatorClasses })
+
+// extensionFunctions maps a function name to the extension providing it.
+var extensionFunctions = buildExtensionIndex(func(ext Extension) []string { return ext.Functions })
+
+// extensionFunctionPrefixes maps a function name prefix to the extension providing it.
+var extensionFunctionPrefixes = buildExtensionIndex(func(ext Extension) []string { return ext.FunctionPrefixes })
+
+func buildExtensionIndex(keys func(Extension) []string) map[string]string {
+	index := make(map[string]string)
+	for _, ext := range postgresExtensions {
+		for _, key := range keys(ext) {
+			// Deterministic on collision: the alphabetically first extension wins.
+			if existing, ok := index[key]; ok && existing < ext.Name {
+				continue
+			}
+			index[key] = ext.Name
+		}
+	}
+	return index
+}
+
+// LookupExtension returns the registered extension by name.
+func LookupExtension(name string) (Extension, bool) {
+	ext, ok := postgresExtensions[strings.ToLower(strings.TrimSpace(name))]
+	return ext, ok
+}
+
+// IsKnownExtension reports whether the named extension is registered.
+func IsKnownExtension(name string) bool {
+	_, ok := LookupExtension(name)
+	return ok
+}
+
+// GetExtensions returns every registered extension name, sorted.
+func GetExtensions() []string {
+	names := make([]string, 0, len(postgresExtensions))
+	for name := range postgresExtensions {
+		names = append(names, name)
+	}
+	sort.Strings(names)
+	return names
+}
+
+// IndexMethodExtension returns the extension providing an index access method
+// ("hnsw" -> "vector", "vchordrq" -> "vchord"). Built-in methods return "".
+func IndexMethodExtension(method string) string {
+	return extensionIndexMethods[strings.ToLower(strings.TrimSpace(method))]
+}
+
+// OperatorClassExtension returns the extension providing an operator class
+// ("gin_trgm_ops" -> "pg_trgm"). Built-in operator classes return "".
+func OperatorClassExtension(opClass string) string {
+	return extensionOperatorClasses[strings.ToLower(strings.TrimSpace(opClass))]
+}
+
+// ExtensionsForExpression returns the extensions whose functions appear in a SQL
+// expression such as a column default, check constraint, index predicate, or view body.
+// The result is sorted and deduplicated.
+func ExtensionsForExpression(expression string) []string {
+	if strings.TrimSpace(expression) == "" {
+		return nil
+	}
+
+	lower := strings.ToLower(expression)
+	found := make(map[string]bool)
+
+	for _, call := range sqlFunctionCalls(lower) {
+		if ext, ok := extensionFunctions[call]; ok {
+			found[ext] = true
+			continue
+		}
+		for prefix, ext := range extensionFunctionPrefixes {
+			if strings.HasPrefix(call, prefix) {
+				found[ext] = true
+				break
+			}
+		}
+	}
+
+	if len(found) == 0 {
+		return nil
+	}
+
+	names := make([]string, 0, len(found))
+	for name := range found {
+		names = append(names, name)
+	}
+	sort.Strings(names)
+	return names
+}
+
+// sqlFunctionCalls returns the lowercase names of every function call in an expression.
+// A call is an identifier (optionally schema-qualified) immediately followed by "(".
+func sqlFunctionCalls(lowerExpression string) []string {
+	calls := make([]string, 0, 4)
+	end := 0
+
+	for i := 0; i < len(lowerExpression); i++ {
+		if lowerExpression[i] != '(' {
+			continue
+		}
+
+		end = i
+		// Allow whitespace between the identifier and its opening parenthesis.
+		for end > 0 && isSQLSpace(lowerExpression[end-1]) {
+			end--
+		}
+
+		start := end
+		for start > 0 && isSQLIdentifierByte(lowerExpression[start-1]) {
+			start--
+		}
+		if start == end {
+			continue
+		}
+		// A leading digit means this is not an identifier (e.g. "2(").
+		if lowerExpression[start] >= '0' && lowerExpression[start] <= '9' {
+			continue
+		}
+		calls = append(calls, lowerExpression[start:end])
+	}
+
+	return calls
+}
+
+func isSQLIdentifierByte(b byte) bool {
+	switch {
+	case b >= 'a' && b <= 'z', b >= 'A' && b <= 'Z', b >= '0' && b <= '9':
+		return true
+	case b == '_', b == '.':
+		return true
+	default:
+		return false
+	}
+}
+
+func isSQLSpace(b byte) bool {
+	return b == ' ' || b == '\t' || b == '\n' || b == '\r'
+}
+
+// SortExtensions orders extension names so that dependencies come first (postgis before
+// postgis_topology, vector before vchord), with alphabetical order breaking ties.
+// Duplicates are removed; unknown names are kept and sorted alphabetically.
+func SortExtensions(names []string) []string {
+	unique := make(map[string]bool, len(names))
+	for _, name := range names {
+		name = strings.ToLower(strings.TrimSpace(name))
+		if name != "" {
+			unique[name] = true
+		}
+	}
+	if len(unique) == 0 {
+		return nil
+	}
+
+	pending := make([]string, 0, len(unique))
+	for name := range unique {
+		pending = append(pending, name)
+	}
+	sort.Strings(pending)
+
+	sorted := make([]string, 0, len(pending))
+	emitted := make(map[string]bool, len(pending))
+
+	var emit func(name string, seen map[string]bool)
+	emit = func(name string, seen map[string]bool) {
+		if emitted[name] || seen[name] {
+			return
+		}
+		seen[name] = true
+
+		if ext, ok := LookupExtension(name); ok {
+			for _, dependency := range ext.Requires {
+				// Only order dependencies that are actually being created.
+				if unique[dependency] {
+					emit(dependency, seen)
+				}
+			}
+		}
+
+		emitted[name] = true
+		sorted = append(sorted, name)
+	}
+
+	for _, name := range pending {
+		emit(name, make(map[string]bool))
+	}
+	return sorted
+}
+
+// ExtensionDependencies returns the extensions a given extension requires, sorted.
+func ExtensionDependencies(name string) []string {
+	ext, ok := LookupExtension(name)
+	if !ok || len(ext.Requires) == 0 {
+		return nil
+	}
+	requires := append([]string(nil), ext.Requires...)
+	sort.Strings(requires)
+	return requires
+}
+
+// QuoteExtensionName quotes an extension name when it is not a bare SQL identifier,
+// e.g. uuid-ossp -> "uuid-ossp".
+func QuoteExtensionName(name string) string {
+	name = strings.TrimSpace(name)
+	if name == "" {
+		return ""
+	}
+	for i := 0; i < len(name); i++ {
+		b := name[i]
+		switch {
+		case b >= 'a' && b <= 'z', b == '_':
+		case b >= '0' && b <= '9' && i > 0:
+		default:
+			return `"` + strings.ReplaceAll(name, `"`, `""`) + `"`
+		}
+	}
+	return name
+}

pkg/pgsql/extensions_test.go

@@ -0,0 +1,165 @@
+package pgsql
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func TestExtensionRegistryConsistency(t *testing.T) {
+	for name, ext := range postgresExtensions {
+		if name != ext.Name {
+			t.Errorf("extension registered as %q has Name %q", name, ext.Name)
+		}
+		if name != strings.ToLower(name) {
+			t.Errorf("extension %q must be registered lowercase", name)
+		}
+		if ext.Description == "" || ext.Category == "" {
+			t.Errorf("extension %q is missing a category or description", name)
+		}
+		for _, dependency := range ext.Requires {
+			if !IsKnownExtension(dependency) {
+				t.Errorf("extension %q requires unregistered extension %q", name, dependency)
+			}
+		}
+	}
+}
+
+// Every extension named by a type in the type registry must itself be registered,
+// otherwise a column type would ask for a CREATE EXTENSION nothing knows how to order.
+func TestTypeExtensionsAreRegistered(t *testing.T) {
+	for typeName, spec := range postgresBaseTypes {
+		if spec.Extension == "" {
+			continue
+		}
+		if !IsKnownExtension(spec.Extension) {
+			t.Errorf("type %q declares unregistered extension %q", typeName, spec.Extension)
+		}
+	}
+}
+
+func TestIndexMethodExtension(t *testing.T) {
+	tests := map[string]string{
+		"hnsw":     "vector",
+		"ivfflat":  "vector",
+		"HNSW":     "vector",
+		"vchordrq": "vchord",
+		"vchordg":  "vchord",
+		"bm25":     "pg_search",
+		"btree":    "",
+		"gin":      "",
+		"":         "",
+	}
+
+	for method, want := range tests {
+		if got := IndexMethodExtension(method); got != want {
+			t.Errorf("IndexMethodExtension(%q) = %q, want %q", method, got, want)
+		}
+	}
+}
+
+func TestOperatorClassExtension(t *testing.T) {
+	tests := map[string]string{
+		"gin_trgm_ops":         "pg_trgm",
+		"gist_trgm_ops":        "pg_trgm",
+		"vector_cosine_ops":    "vector",
+		"halfvec_l2_ops":       "vector",
+		"gist_ltree_ops":       "ltree",
+		"gist_geometry_ops_2d": "postgis",
+		"jsonb_path_ops":       "",
+		"array_ops":            "",
+		"":                     "",
+	}
+
+	for opClass, want := range tests {
+		if got := OperatorClassExtension(opClass); got != want {
+			t.Errorf("OperatorClassExtension(%q) = %q, want %q", opClass, got, want)
+		}
+	}
+}
+
+func TestExtensionsForExpression(t *testing.T) {
+	tests := []struct {
+		name       string
+		expression string
+		want       []string
+	}{
+		{"empty", "", nil},
+		{"no functions", "status = 'active'", nil},
+		{"builtin only", "now()", nil},
+		{"uuid-ossp default", "uuid_generate_v4()", []string{"uuid-ossp"}},
+		{"gen_random_uuid is builtin", "gen_random_uuid()", nil},
+		{"pgcrypto", "crypt(password, gen_salt('bf'))", []string{"pgcrypto"}},
+		{"postgis prefix", "ST_Area(geom) > 0", []string{"postgis"}},
+		{"paradedb prefix", "paradedb.snippet(body)", []string{"pg_search"}},
+		{"jsonschema", "json_matches_schema('{}', payload)", []string{"pg_jsonschema"}},
+		{"whitespace before paren", "unaccent ('crème')", []string{"unaccent"}},
+		{"multiple sorted", "ST_X(geom) = levenshtein(a, b)::float", []string{"fuzzystrmatch", "postgis"}},
+		{"column named like function", "similarity_score > 0.5", nil},
+		{"numeric prefix ignored", "2(3)", nil},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := ExtensionsForExpression(tt.expression); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("ExtensionsForExpression(%q) = %v, want %v", tt.expression, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestSortExtensions(t *testing.T) {
+	tests := []struct {
+		name  string
+		input []string
+		want  []string
+	}{
+		{"empty", nil, nil},
+		{"alphabetical", []string{"pg_trgm", "citext"}, []string{"citext", "pg_trgm"}},
+		{"deduplicated", []string{"vector", "vector", " VECTOR "}, []string{"vector"}},
+		{"dependency first", []string{"vchord", "vector"}, []string{"vector", "vchord"}},
+		{
+			"postgis dependants",
+			[]string{"postgis_topology", "pgrouting", "postgis"},
+			[]string{"postgis", "pgrouting", "postgis_topology"},
+		},
+		{"dependency not requested", []string{"vchord"}, []string{"vchord"}},
+		{"unknown names kept", []string{"zzz_custom", "citext"}, []string{"citext", "zzz_custom"}},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := SortExtensions(tt.input); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("SortExtensions(%v) = %v, want %v", tt.input, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestQuoteExtensionName(t *testing.T) {
+	tests := map[string]string{
+		"vector":    "vector",
+		"pg_trgm":   "pg_trgm",
+		"uuid-ossp": `"uuid-ossp"`,
+		"PostGIS":   `"PostGIS"`,
+		"":          "",
+	}
+
+	for name, want := range tests {
+		if got := QuoteExtensionName(name); got != want {
+			t.Errorf("QuoteExtensionName(%q) = %q, want %q", name, got, want)
+		}
+	}
+}
+
+func TestExtensionDependencies(t *testing.T) {
+	if got := ExtensionDependencies("vchord"); !reflect.DeepEqual(got, []string{"vector"}) {
+		t.Errorf("ExtensionDependencies(vchord) = %v, want [vector]", got)
+	}
+	if got := ExtensionDependencies("citext"); got != nil {
+		t.Errorf("ExtensionDependencies(citext) = %v, want nil", got)
+	}
+	if got := ExtensionDependencies("not_an_extension"); got != nil {
+		t.Errorf("ExtensionDependencies(not_an_extension) = %v, want nil", got)
+	}
+}

pkg/pgsql/index_options.go

@@ -0,0 +1,248 @@
+package pgsql
+
+import (
+	"strconv"
+	"strings"
+)
+
+// Index access-method storage parameters, the WITH (...) clause of CREATE INDEX. RelSpec
+// carries them through the model in Index.Comment, so the parsing here is deliberately
+// strict: only well-formed "key = value" pairs survive, and comment prose is discarded.
+//
+// Value forms accepted:
+//   - bare tokens: lists=100, m=16, deduplicate_items=true
+//   - quoted strings: key_field='id' (pg_search bm25)
+//   - dollar-quoted blocks: options=$$ [build.internal] lists=[4096] $$ (vchord)
+
+// ExtractWithClause returns the contents of the first WITH (...) clause in s, without the
+// surrounding parentheses. Parentheses inside quoted and dollar-quoted values are ignored,
+// so a vchord TOML block survives intact. Returns "" when there is no WITH clause.
+func ExtractWithClause(s string) string {
+	lower := strings.ToLower(s)
+
+	for offset := 0; ; {
+		idx := strings.Index(lower[offset:], "with")
+		if idx < 0 {
+			return ""
+		}
+		start := offset + idx
+		offset = start + 4
+
+		// "with" must stand as its own word.
+		if start > 0 && isSQLIdentifierByte(s[start-1]) {
+			continue
+		}
+
+		pos := offset
+		for pos < len(s) && isSQLSpace(s[pos]) {
+			pos++
+		}
+		if pos >= len(s) || s[pos] != '(' {
+			continue
+		}
+
+		if end, ok := matchClosingParen(s, pos); ok {
+			return s[pos+1 : end]
+		}
+		return ""
+	}
+}
+
+// matchClosingParen returns the index of the ')' matching the '(' at open, skipping over
+// quoted and dollar-quoted spans.
+func matchClosingParen(s string, open int) (int, bool) {
+	depth := 0
+	for i := open; i < len(s); i++ {
+		switch s[i] {
+		case '\'':
+			end, ok := skipQuoted(s, i)
+			if !ok {
+				return 0, false
+			}
+			i = end
+		case '$':
+			if end, ok := skipDollarQuoted(s, i); ok {
+				i = end
+			}
+		case '(':
+			depth++
+		case ')':
+			depth--
+			if depth == 0 {
+				return i, true
+			}
+		}
+	}
+	return 0, false
+}
+
+// skipQuoted returns the index of the closing quote of the single-quoted string starting
+// at start, treating ” as an escaped quote.
+func skipQuoted(s string, start int) (int, bool) {
+	for i := start + 1; i < len(s); i++ {
+		if s[i] != '\'' {
+			continue
+		}
+		if i+1 < len(s) && s[i+1] == '\'' {
+			i++
+			continue
+		}
+		return i, true
+	}
+	return 0, false
+}
+
+// skipDollarQuoted returns the index of the last byte of the dollar-quoted block starting
+// at start ($tag$ … $tag$). Reports false when start does not open one.
+func skipDollarQuoted(s string, start int) (int, bool) {
+	tagEnd := strings.IndexByte(s[start+1:], '$')
+	if tagEnd < 0 {
+		return 0, false
+	}
+	tag := s[start : start+1+tagEnd+1]
+	for i := start + 1; i < len(tag); i++ {
+		if !isSQLIdentifierByte(tag[i]) && tag[i] != '$' {
+			return 0, false
+		}
+	}
+
+	closing := strings.Index(s[start+len(tag):], tag)
+	if closing < 0 {
+		return 0, false
+	}
+	return start + len(tag) + closing + len(tag) - 1, true
+}
+
+// SplitStorageParameters splits a WITH clause body on top-level commas, leaving quoted and
+// dollar-quoted values untouched.
+func SplitStorageParameters(clause string) []string {
+	parts := make([]string, 0, 4)
+	depth := 0
+	start := 0
+
+	for i := 0; i < len(clause); i++ {
+		switch clause[i] {
+		case '\'':
+			if end, ok := skipQuoted(clause, i); ok {
+				i = end
+			}
+		case '$':
+			if end, ok := skipDollarQuoted(clause, i); ok {
+				i = end
+			}
+		case '(', '[':
+			depth++
+		case ')', ']':
+			depth--
+		case ',':
+			if depth == 0 {
+				parts = append(parts, clause[start:i])
+				start = i + 1
+			}
+		}
+	}
+	parts = append(parts, clause[start:])
+
+	trimmed := make([]string, 0, len(parts))
+	for _, part := range parts {
+		if part = strings.TrimSpace(part); part != "" {
+			trimmed = append(trimmed, part)
+		}
+	}
+	return trimmed
+}
+
+// ParseStorageParameter splits one "key = value" storage parameter. It reports false for
+// anything that is not a well-formed parameter, which is how comment prose is filtered out.
+func ParseStorageParameter(part string) (key, value string, ok bool) {
+	key, value, found := strings.Cut(part, "=")
+	if !found {
+		return "", "", false
+	}
+
+	key = strings.ToLower(strings.TrimSpace(key))
+	value = strings.TrimSpace(value)
+	if key == "" || value == "" || !isBareIdentifier(key) {
+		return "", "", false
+	}
+	if !isStorageParameterValue(value) {
+		return "", "", false
+	}
+	return key, value, true
+}
+
+// FormatStorageParameters renders a WITH clause body as a canonical "key = value" list,
+// dropping anything malformed. Returns "" when nothing survives.
+func FormatStorageParameters(clause string) string {
+	params := make([]string, 0, 4)
+	for _, part := range SplitStorageParameters(clause) {
+		key, value, ok := ParseStorageParameter(part)
+		if !ok {
+			continue
+		}
+		params = append(params, key+" = "+value)
+	}
+	return strings.Join(params, ", ")
+}
+
+// NormalizeStorageParameterValue unquotes a value that PostgreSQL rendered as a string but
+// that is really a number, so that pg_indexes output (lists='100') and hand-written models
+// (lists=100) normalize identically. Non-numeric quoted values keep their quotes because
+// some access methods require a string (pg_search's key_field='id').
+func NormalizeStorageParameterValue(value string) string {
+	value = strings.TrimSpace(value)
+	if len(value) < 2 || value[0] != '\'' || value[len(value)-1] != '\'' {
+		return value
+	}
+
+	inner := strings.ReplaceAll(value[1:len(value)-1], "''", "'")
+	if _, err := strconv.ParseFloat(inner, 64); err == nil {
+		return inner
+	}
+	if strings.EqualFold(inner, "true") || strings.EqualFold(inner, "false") {
+		return strings.ToLower(inner)
+	}
+	return value
+}
+
+func isBareIdentifier(s string) bool {
+	if s == "" {
+		return false
+	}
+	for i := 0; i < len(s); i++ {
+		b := s[i]
+		switch {
+		case b >= 'a' && b <= 'z', b >= 'A' && b <= 'Z', b == '_':
+		case b >= '0' && b <= '9' && i > 0:
+		default:
+			return false
+		}
+	}
+	return true
+}
+
+// isStorageParameterValue reports whether value is a bare token, a complete quoted string,
+// or a complete dollar-quoted block.
+func isStorageParameterValue(value string) bool {
+	switch {
+	case value == "":
+		return false
+	case value[0] == '\'':
+		end, ok := skipQuoted(value, 0)
+		return ok && end == len(value)-1
+	case value[0] == '$':
+		end, ok := skipDollarQuoted(value, 0)
+		return ok && end == len(value)-1
+	}
+
+	for i := 0; i < len(value); i++ {
+		b := value[i]
+		switch {
+		case b >= 'a' && b <= 'z', b >= 'A' && b <= 'Z', b >= '0' && b <= '9':
+		case b == '_', b == '.', b == '-', b == '+':
+		default:
+			return false
+		}
+	}
+	return true
+}

pkg/pgsql/index_options_test.go

@@ -0,0 +1,111 @@
+package pgsql
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestExtractWithClause(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  string
+	}{
+		{"empty", "", ""},
+		{"no clause", "opclass=vector_cosine_ops", ""},
+		{"simple", "WITH (lists=100)", "lists=100"},
+		{"lowercase", "with (m = 16, ef_construction = 64)", "m = 16, ef_construction = 64"},
+		{
+			"index definition",
+			"CREATE INDEX i ON t USING ivfflat (embedding vector_cosine_ops) WITH (lists='100')",
+			"lists='100'",
+		},
+		{"paren inside quotes", "with (key_field='id(x)')", "key_field='id(x)'"},
+		{"dollar quoted", "with (options = $$f(x)$$)", "options = $$f(x)$$"},
+		{"word boundary", "swith (lists=100)", ""},
+		{"not followed by paren", "with lists=100", ""},
+		{"unterminated", "with (lists=100", ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := ExtractWithClause(tt.input); got != tt.want {
+				t.Errorf("ExtractWithClause(%q) = %q, want %q", tt.input, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestSplitStorageParameters(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  []string
+	}{
+		{"empty", "", []string{}},
+		{"single", "lists=100", []string{"lists=100"}},
+		{"multiple", "m = 16, ef_construction = 64", []string{"m = 16", "ef_construction = 64"}},
+		{"comma in quotes", "key_field='a,b', m=16", []string{"key_field='a,b'", "m=16"}},
+		{"comma in dollar quotes", "options=$$a,b$$, m=16", []string{"options=$$a,b$$", "m=16"}},
+		{"comma in brackets", "options=[1,2], m=16", []string{"options=[1,2]", "m=16"}},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := SplitStorageParameters(tt.input); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("SplitStorageParameters(%q) = %v, want %v", tt.input, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestParseStorageParameter(t *testing.T) {
+	tests := []struct {
+		name      string
+		input     string
+		wantKey   string
+		wantValue string
+		wantOK    bool
+	}{
+		{"bare", "lists=100", "lists", "100", true},
+		{"spaced and uppercased key", " Lists = 100 ", "lists", "100", true},
+		{"quoted", "key_field='id'", "key_field", "'id'", true},
+		{"dollar quoted", "options=$$a$$", "options", "$$a$$", true},
+		{"boolean", "deduplicate_items=true", "deduplicate_items", "true", true},
+		{"float", "fillfactor=90.5", "fillfactor", "90.5", true},
+		{"no equals", "please drop everything", "", "", false},
+		{"empty value", "lists=", "", "", false},
+		{"quoted key rejected", "'lists'=100", "", "", false},
+		{"injection rejected", "lists=100); drop table t", "", "", false},
+		{"unterminated quote rejected", "key_field='id", "", "", false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			key, value, ok := ParseStorageParameter(tt.input)
+			if key != tt.wantKey || value != tt.wantValue || ok != tt.wantOK {
+				t.Errorf("ParseStorageParameter(%q) = (%q, %q, %v), want (%q, %q, %v)",
+					tt.input, key, value, ok, tt.wantKey, tt.wantValue, tt.wantOK)
+			}
+		})
+	}
+}
+
+func TestNormalizeStorageParameterValue(t *testing.T) {
+	tests := map[string]string{
+		"'100'":   "100",
+		"'90.5'":  "90.5",
+		"'true'":  "true",
+		"'id'":    "'id'",
+		"100":     "100",
+		"$$a,b$$": "$$a,b$$",
+		"'":       "'",
+		"''":      "''",
+	}
+
+	for input, want := range tests {
+		if got := NormalizeStorageParameterValue(input); got != want {
+			t.Errorf("NormalizeStorageParameterValue(%q) = %q, want %q", input, got, want)
+		}
+	}
+}

pkg/pgsql/types_registry.go

@@ -2,6 +2,7 @@ package pgsql
 
 import (
 	"sort"
+	"strconv"
 	"strings"
 )
 
@@ -9,6 +10,14 @@ import (
 type TypeSpec struct {
 	SupportsLength    bool
 	SupportsPrecision bool
+
+	// SupportsTypeModifier marks types whose "(...)" modifier is opaque and must be
+	// preserved verbatim (e.g. vector(1536), geometry(Point,4326)) instead of being
+	// decomposed into Length/Precision/Scale.
+	SupportsTypeModifier bool
+
+	// Extension is the PostgreSQL extension providing the type; empty for built-ins.
+	Extension string
 }
 
 var postgresBaseTypes = map[string]TypeSpec{
@@ -104,14 +113,28 @@ var postgresBaseTypes = map[string]TypeSpec{
 	"void":   {},
 
 	// Common extensions
-	"citext":    {},
-	"hstore":    {},
-	"ltree":     {},
-	"lquery":    {},
-	"ltxtquery": {},
-	"vector":    {}, // pgvector: keep explicit modifier form (vector(dim))
-	"halfvec":   {}, // pgvector: keep explicit modifier form (halfvec(dim))
-	"sparsevec": {}, // pgvector: keep explicit modifier form (sparsevec(dim))
+	"citext":    {Extension: "citext"},
+	"hstore":    {Extension: "hstore"},
+	"ltree":     {Extension: "ltree"},
+	"lquery":    {Extension: "ltree"},
+	"ltxtquery": {Extension: "ltree"},
+
+	// pgvector: modifier form is opaque (vector(dim), sparsevec(dim))
+	"vector":    {SupportsTypeModifier: true, Extension: "vector"},
+	"halfvec":   {SupportsTypeModifier: true, Extension: "vector"},
+	"sparsevec": {SupportsTypeModifier: true, Extension: "vector"},
+
+	// PostGIS: geometry/geography carry an opaque modifier (geometry(PointZ,4326))
+	"geometry":      {SupportsTypeModifier: true, Extension: "postgis"},
+	"geography":     {SupportsTypeModifier: true, Extension: "postgis"},
+	"box2d":         {Extension: "postgis"},
+	"box3d":         {Extension: "postgis"},
+	"geometry_dump": {Extension: "postgis"},
+	"geomval":       {Extension: "postgis"},
+	"spheroid":      {Extension: "postgis"},
+	"valid_detail":  {Extension: "postgis"},
+	"raster":        {SupportsTypeModifier: true, Extension: "postgis_raster"},
+	"topogeometry":  {Extension: "postgis_topology"},
 }
 
 var postgresTypeAliases = map[string]string{
@@ -346,3 +369,72 @@ func stripArraySuffixes(t string) string {
 func normalizeTypeToken(t string) string {
 	return strings.Join(strings.Fields(strings.TrimSpace(t)), " ")
 }
+
+// SupportsTypeModifier reports if this SQL type carries an opaque "(...)" modifier
+// that must be preserved verbatim (e.g. vector(1536), geometry(Point,4326)).
+func SupportsTypeModifier(sqlType string) bool {
+	base := CanonicalizeBaseType(ExtractBaseTypeLower(sqlType))
+	spec, ok := postgresBaseTypes[base]
+	return ok && spec.SupportsTypeModifier
+}
+
+// TypeExtension returns the PostgreSQL extension providing the given type
+// ("postgis", "vector", "citext", …). Built-in types return "".
+func TypeExtension(sqlType string) string {
+	base := CanonicalizeBaseType(ExtractBaseTypeLower(sqlType))
+	return postgresBaseTypes[base].Extension
+}
+
+// IsSpatialType reports whether the type comes from PostGIS (geometry, geography,
+// raster, topogeometry, …).
+func IsSpatialType(sqlType string) bool {
+	return strings.HasPrefix(TypeExtension(sqlType), "postgis")
+}
+
+// IsVectorType reports whether the type comes from pgvector (vector, halfvec, sparsevec).
+func IsVectorType(sqlType string) bool {
+	return TypeExtension(sqlType) == "vector"
+}
+
+// TypeModifier returns the raw "(...)" modifier of a SQL type without the parentheses,
+// or "" when the type has none. Array suffixes are ignored.
+// Example: geometry(PointZ,4326)[] -> "PointZ,4326".
+func TypeModifier(sqlType string) string {
+	t := stripArraySuffixes(normalizeTypeToken(sqlType))
+	start := strings.Index(t, "(")
+	end := strings.LastIndex(t, ")")
+	if start < 0 || end < start {
+		return ""
+	}
+	return strings.TrimSpace(t[start+1 : end])
+}
+
+// SpatialSRID returns the SRID declared in a PostGIS type modifier, or 0 when absent.
+// Example: geometry(Point,4326) -> 4326.
+func SpatialSRID(sqlType string) int {
+	if !IsSpatialType(sqlType) {
+		return 0
+	}
+	parts := strings.Split(TypeModifier(sqlType), ",")
+	if len(parts) < 2 {
+		return 0
+	}
+	srid, err := strconv.Atoi(strings.TrimSpace(parts[len(parts)-1]))
+	if err != nil {
+		return 0
+	}
+	return srid
+}
+
+// SpatialGeometryType returns the geometry subtype declared in a PostGIS type modifier
+// ("Point", "MultiPolygonZ", …), or "" when absent.
+func SpatialGeometryType(sqlType string) string {
+	if !IsSpatialType(sqlType) {
+		return ""
+	}
+	modifier := TypeModifier(sqlType)
+	if modifier == "" {
+		return ""
+	}
+	return strings.TrimSpace(strings.Split(modifier, ",")[0])
+}

pkg/pgsql/types_registry_test.go

@@ -145,3 +145,104 @@ func TestEquivalentSQLTypeVariants(t *testing.T) {
 		})
 	}
 }
+
+func TestExtensionTypes(t *testing.T) {
+	tests := []struct {
+		name          string
+		sqlType       string
+		wantKnown     bool
+		wantExtension string
+		wantSpatial   bool
+		wantVector    bool
+		wantModifier  bool
+	}{
+		{"geometry with modifier", "geometry(Point,4326)", true, "postgis", true, false, true},
+		{"geography", "geography", true, "postgis", true, false, true},
+		{"geometry array", "geometry[]", true, "postgis", true, false, true},
+		{"box2d", "box2d", true, "postgis", true, false, false},
+		{"raster", "raster", true, "postgis_raster", true, false, true},
+		{"topogeometry", "topogeometry", true, "postgis_topology", true, false, false},
+		{"vector", "vector(1536)", true, "vector", false, true, true},
+		{"halfvec", "halfvec(768)", true, "vector", false, true, true},
+		{"sparsevec", "sparsevec(1000)", true, "vector", false, true, true},
+		{"citext", "citext", true, "citext", false, false, false},
+		{"builtin text", "text", true, "", false, false, false},
+		{"builtin point is not postgis", "point", true, "", false, false, false},
+		{"unknown type", "mytype", false, "", false, false, false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := IsKnownPostgresType(tt.sqlType); got != tt.wantKnown {
+				t.Errorf("IsKnownPostgresType(%q) = %v, want %v", tt.sqlType, got, tt.wantKnown)
+			}
+			if got := TypeExtension(tt.sqlType); got != tt.wantExtension {
+				t.Errorf("TypeExtension(%q) = %q, want %q", tt.sqlType, got, tt.wantExtension)
+			}
+			if got := IsSpatialType(tt.sqlType); got != tt.wantSpatial {
+				t.Errorf("IsSpatialType(%q) = %v, want %v", tt.sqlType, got, tt.wantSpatial)
+			}
+			if got := IsVectorType(tt.sqlType); got != tt.wantVector {
+				t.Errorf("IsVectorType(%q) = %v, want %v", tt.sqlType, got, tt.wantVector)
+			}
+			if got := SupportsTypeModifier(tt.sqlType); got != tt.wantModifier {
+				t.Errorf("SupportsTypeModifier(%q) = %v, want %v", tt.sqlType, got, tt.wantModifier)
+			}
+		})
+	}
+}
+
+func TestExtensionTypesDoNotSupportLengthOrPrecision(t *testing.T) {
+	for _, sqlType := range []string{"geometry(Point,4326)", "geography", "vector(1536)", "halfvec(768)"} {
+		if SupportsLength(sqlType) {
+			t.Errorf("SupportsLength(%q) = true, want false", sqlType)
+		}
+		if SupportsPrecision(sqlType) {
+			t.Errorf("SupportsPrecision(%q) = true, want false", sqlType)
+		}
+	}
+}
+
+func TestSpatialTypeModifier(t *testing.T) {
+	tests := []struct {
+		sqlType      string
+		wantModifier string
+		wantGeomType string
+		wantSRID     int
+	}{
+		{"geometry(Point,4326)", "Point,4326", "Point", 4326},
+		{"geometry(MultiPolygonZ, 3857)", "MultiPolygonZ, 3857", "MultiPolygonZ", 3857},
+		{"geography(Point)", "Point", "Point", 0},
+		{"geometry", "", "", 0},
+		{"geometry(Point,4326)[]", "Point,4326", "Point", 4326},
+		{"vector(1536)", "1536", "", 0},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.sqlType, func(t *testing.T) {
+			if got := TypeModifier(tt.sqlType); got != tt.wantModifier {
+				t.Errorf("TypeModifier() = %q, want %q", got, tt.wantModifier)
+			}
+			if got := SpatialGeometryType(tt.sqlType); got != tt.wantGeomType {
+				t.Errorf("SpatialGeometryType() = %q, want %q", got, tt.wantGeomType)
+			}
+			if got := SpatialSRID(tt.sqlType); got != tt.wantSRID {
+				t.Errorf("SpatialSRID() = %d, want %d", got, tt.wantSRID)
+			}
+		})
+	}
+}
+
+func TestNormalizeEquivalentSQLTypePreservesExtensionModifiers(t *testing.T) {
+	tests := map[string]string{
+		"geometry(Point,4326)": "geometry(Point,4326)",
+		"vector(1536)":         "vector(1536)",
+		"geography(Point)[]":   "geography(Point)[]",
+	}
+
+	for input, want := range tests {
+		if got := NormalizeEquivalentSQLType(input); got != want {
+			t.Errorf("NormalizeEquivalentSQLType(%q) = %q, want %q", input, got, want)
+		}
+	}
+}

pkg/readers/dbml/reader_test.go

@@ -863,6 +863,13 @@ func TestParseColumn_PostgresTypes(t *testing.T) {
 			wantName: "embedding",
 			wantType: "vector(1536)",
 		},
+		{
+			name:        "postgis geometry with type modifier",
+			line:        "location geometry(Point,4326) [not null]",
+			wantName:    "location",
+			wantType:    "geometry(Point,4326)",
+			wantNotNull: true,
+		},
 		{
 			name:     "multi word timestamp type",
 			line:     "published_at timestamp with time zone",

pkg/readers/pgsql/README.md

@@ -128,6 +128,27 @@ sessions so they are identifiable in `pg_stat_activity`. If you provide
 - Sequence properties
 - Associated tables
 
+## Extension Types (PostGIS, pgvector)
+
+- Extension column types keep their catalog-formatted form: `geometry(Point,4326)`,
+  `geography(Point)`, `vector(1536)`, `halfvec(768)`, `citext`, arrays included.
+- Built-in types are canonicalized and their dimensions moved to
+  `Column.Length` / `Precision` / `Scale`; extension modifiers stay in `Column.Type`.
+- Index access methods are read from the definition as-is: `gist`, `spgist`, `brin`, `hnsw`,
+  `ivfflat`, `vchordrq`, `vchordg`, `bm25`.
+- Operator class and `WITH (...)` parameters have no model field, so they are stored in
+  `Index.Comment` in the form the PostgreSQL writer reads back:
+
+  ```
+  opclass=vector_cosine_ops; with (m=16, ef_construction=64)
+  ```
+
+  Ordering modifiers (`DESC`, `NULLS LAST`, `COLLATE`) are not treated as operator classes.
+  Numeric parameter values are unquoted (`lists='100'` -> `lists=100`); string values keep
+  their quotes (`key_field='id'`), and dollar-quoted values are preserved whole.
+- Installed extensions are read from `pg_extension` into `schema.Metadata["extensions"]`
+  (only extensions RelSpec recognizes), so a read/write round-trip re-creates them.
+
 ## Notes
 
 - Requires PostgreSQL connection permissions

pkg/readers/pgsql/queries.go

@@ -5,6 +5,7 @@ import (
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 )
 
 // querySchemas retrieves all non-system schemas from the database
@@ -46,6 +47,41 @@ func (r *Reader) querySchemas() ([]*models.Schema, error) {
 	return schemas, rows.Err()
 }
 
+// queryExtensions retrieves the extensions installed into a schema. Only extensions RelSpec
+// recognizes are kept, so a round-trip never emits a CREATE EXTENSION the writer cannot
+// order; plpgsql is not registered and is therefore skipped along with other built-ins.
+func (r *Reader) queryExtensions(schemaName string) ([]string, error) {
+	query := `
+		SELECT e.extname
+		FROM pg_extension e
+		JOIN pg_namespace n ON n.oid = e.extnamespace
+		WHERE n.nspname = $1
+		ORDER BY e.extname
+	`
+
+	rows, err := r.conn.Query(r.ctx, query, schemaName)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	extensions := make([]string, 0)
+	for rows.Next() {
+		var name string
+		if err := rows.Scan(&name); err != nil {
+			return nil, err
+		}
+		if pgsql.IsKnownExtension(name) {
+			extensions = append(extensions, name)
+		}
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+
+	return pgsql.SortExtensions(extensions), nil
+}
+
 // queryTables retrieves all tables for a given schema
 func (r *Reader) queryTables(schemaName string) ([]*models.Table, error) {
 	query := `
@@ -597,6 +633,7 @@ func (r *Reader) parseIndexDefinition(indexName, tableName, schema, indexDef str
 	}
 
 	// Extract columns - pattern: (column1, column2, ...)
+	opClass := ""
 	columnsRegex := regexp.MustCompile(`\(([^)]+)\)`)
 	if matches := columnsRegex.FindStringSubmatch(indexDef); len(matches) > 1 {
 		columnsStr := matches[1]
@@ -604,8 +641,17 @@ func (r *Reader) parseIndexDefinition(indexName, tableName, schema, indexDef str
 		columnParts := strings.Split(columnsStr, ",")
 		for _, col := range columnParts {
 			col = strings.TrimSpace(col)
+			fields := strings.Fields(col)
+			if len(fields) == 0 {
+				continue
+			}
+			// Remember an explicit operator class (e.g. "embedding vector_cosine_ops")
+			// so the writer can reproduce it; ordering modifiers are not operator classes.
+			if opClass == "" && len(fields) > 1 {
+				opClass = extractIndexOperatorClass(fields[1:])
+			}
 			// Remove any ordering (ASC/DESC) or other modifiers
-			col = strings.Fields(col)[0]
+			col = fields[0]
 			// Remove parentheses if it's an expression
 			if !strings.Contains(col, "(") {
 				index.Columns = append(index.Columns, col)
@@ -613,6 +659,15 @@ func (r *Reader) parseIndexDefinition(indexName, tableName, schema, indexDef str
 		}
 	}
 
+	// Extract access method storage parameters, e.g. WITH (lists='100')
+	storageParams := normalizeIndexStorageParams(pgsql.ExtractWithClause(indexDef))
+
+	// Operator class and storage parameters have no dedicated model fields; carry them in
+	// the comment hint the PostgreSQL writer reads back.
+	if hint := buildIndexHint(opClass, storageParams); hint != "" && index.Comment == "" {
+		index.Comment = hint
+	}
+
 	// Extract WHERE clause for partial indexes
 	whereRegex := regexp.MustCompile(`WHERE\s+(.+)$`)
 	if matches := whereRegex.FindStringSubmatch(indexDef); len(matches) > 1 {
@@ -622,6 +677,52 @@ func (r *Reader) parseIndexDefinition(indexName, tableName, schema, indexDef str
 	return index, nil
 }
 
+// indexOrderingKeywords are column modifiers that are not operator classes.
+var indexOrderingKeywords = map[string]bool{
+	"asc": true, "desc": true, "nulls": true, "first": true, "last": true, "collate": true,
+}
+
+// extractIndexOperatorClass picks the operator class out of a column's trailing modifiers.
+// Returns "" when the modifiers are only ordering keywords.
+func extractIndexOperatorClass(modifiers []string) string {
+	for _, modifier := range modifiers {
+		lower := strings.ToLower(strings.TrimSpace(modifier))
+		if lower == "" || indexOrderingKeywords[lower] {
+			continue
+		}
+		return lower
+	}
+	return ""
+}
+
+// normalizeIndexStorageParams rewrites "m='16', ef_construction='64'" as "m=16,
+// ef_construction=64". Non-numeric values keep their quotes because some access methods
+// require a string literal (pg_search's key_field='id').
+func normalizeIndexStorageParams(params string) string {
+	normalized := make([]string, 0, 4)
+	for _, part := range pgsql.SplitStorageParameters(params) {
+		key, value, ok := pgsql.ParseStorageParameter(part)
+		if !ok {
+			continue
+		}
+		normalized = append(normalized, key+"="+pgsql.NormalizeStorageParameterValue(value))
+	}
+	return strings.Join(normalized, ", ")
+}
+
+// buildIndexHint renders the operator class and storage parameters in the form the
+// PostgreSQL writer parses back out of an index comment.
+func buildIndexHint(opClass, storageParams string) string {
+	parts := make([]string, 0, 2)
+	if opClass != "" {
+		parts = append(parts, "opclass="+opClass)
+	}
+	if storageParams != "" {
+		parts = append(parts, "with ("+storageParams+")")
+	}
+	return strings.Join(parts, "; ")
+}
+
 // normalizePostgresDefault converts a raw PostgreSQL column_default expression into the
 // unquoted string value that the model convention expects. PostgreSQL stores string
 // literal defaults as 'value' or 'value'::type (e.g. '{}'::text[]), while every other

pkg/readers/pgsql/reader.go

@@ -88,6 +88,18 @@ func (r *Reader) ReadDatabase() (*models.Database, error) {
 		}
 		schema.Sequences = sequences
 
+		// Query extensions installed into this schema
+		extensions, err := r.queryExtensions(schema.Name)
+		if err != nil {
+			return nil, fmt.Errorf("failed to query extensions for schema %s: %w", schema.Name, err)
+		}
+		if len(extensions) > 0 {
+			if schema.Metadata == nil {
+				schema.Metadata = make(map[string]any)
+			}
+			schema.Metadata["extensions"] = extensions
+		}
+
 		// Query columns for tables and views
 		columnsMap, err := r.queryColumns(schema.Name)
 		if err != nil {
@@ -278,11 +290,6 @@ func (r *Reader) mapDataType(pgType, udtName, formattedType string, hasNextval b
 		}
 	}
 
-	// information_schema reports arrays generically as "ARRAY" with udt_name like "_text".
-	if strings.EqualFold(pgType, "ARRAY") && strings.HasPrefix(udtName, "_") && len(udtName) > 1 {
-		return udtName[1:] + "[]"
-	}
-
 	// Use the database-formatted type when available. For known built-in types, strip
 	// embedded dimensions (they are stored in column.Length/Precision/Scale separately).
 	// For unknown/custom types, keep the full formatted string (e.g. vector(1536)).
@@ -303,6 +310,13 @@ func (r *Reader) mapDataType(pgType, udtName, formattedType string, hasNextval b
 		return formattedType
 	}
 
+	// information_schema reports arrays generically as "ARRAY" with udt_name like "_text".
+	// Only reached when the catalog-formatted type is unavailable, which is the one case
+	// where the element modifier (e.g. geometry(Point,4326)[]) cannot be recovered.
+	if strings.EqualFold(pgType, "ARRAY") && strings.HasPrefix(udtName, "_") && len(udtName) > 1 {
+		return udtName[1:] + "[]"
+	}
+
 	// Fall back to normalizing the information_schema type name directly.
 	canonical := pgsql.NormalizePGType(normalizedPGType)
 	if pgsql.IsKnownPGBaseType(canonical) {

pkg/readers/pgsql/reader_test.go

@@ -392,3 +392,101 @@ func BenchmarkReader_ReadDatabase(b *testing.B) {
 		}
 	}
 }
+
+func TestParseIndexDefinition_ExtensionIndexes(t *testing.T) {
+	reader := &Reader{}
+
+	tests := []struct {
+		name        string
+		indexDef    string
+		wantType    string
+		wantColumns []string
+		wantComment string
+	}{
+		{
+			name:        "hnsw vector index with storage parameters",
+			indexDef:    "CREATE INDEX idx_docs_embedding ON public.docs USING hnsw (embedding vector_cosine_ops) WITH (m='16', ef_construction='64')",
+			wantType:    "hnsw",
+			wantColumns: []string{"embedding"},
+			wantComment: "opclass=vector_cosine_ops; with (m=16, ef_construction=64)",
+		},
+		{
+			name:        "ivfflat vector index",
+			indexDef:    "CREATE INDEX idx_docs_embedding ON public.docs USING ivfflat (embedding vector_l2_ops) WITH (lists='100')",
+			wantType:    "ivfflat",
+			wantColumns: []string{"embedding"},
+			wantComment: "opclass=vector_l2_ops; with (lists=100)",
+		},
+		{
+			name:        "gist geometry index with default operator class",
+			indexDef:    "CREATE INDEX idx_places_geom ON public.places USING gist (geom)",
+			wantType:    "gist",
+			wantColumns: []string{"geom"},
+			wantComment: "",
+		},
+		{
+			name:        "gist geometry index with explicit operator class",
+			indexDef:    "CREATE INDEX idx_places_geom ON public.places USING gist (geom gist_geometry_ops_nd)",
+			wantType:    "gist",
+			wantColumns: []string{"geom"},
+			wantComment: "opclass=gist_geometry_ops_nd",
+		},
+		{
+			name:        "btree ordering modifiers are not operator classes",
+			indexDef:    "CREATE INDEX idx_users_created ON public.users USING btree (created_at DESC NULLS LAST)",
+			wantType:    "btree",
+			wantColumns: []string{"created_at"},
+			wantComment: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			index, err := reader.parseIndexDefinition("idx", "tbl", "public", tt.indexDef)
+			if err != nil {
+				t.Fatalf("parseIndexDefinition() error = %v", err)
+			}
+
+			if index.Type != tt.wantType {
+				t.Errorf("Type = %q, want %q", index.Type, tt.wantType)
+			}
+			if len(index.Columns) != len(tt.wantColumns) {
+				t.Fatalf("Columns = %v, want %v", index.Columns, tt.wantColumns)
+			}
+			for i, col := range tt.wantColumns {
+				if index.Columns[i] != col {
+					t.Errorf("Columns[%d] = %q, want %q", i, index.Columns[i], col)
+				}
+			}
+			if index.Comment != tt.wantComment {
+				t.Errorf("Comment = %q, want %q", index.Comment, tt.wantComment)
+			}
+		})
+	}
+}
+
+func TestMapDataType_ExtensionTypesPreserveModifiers(t *testing.T) {
+	reader := &Reader{}
+
+	tests := []struct {
+		name          string
+		pgType        string
+		udtName       string
+		formattedType string
+		want          string
+	}{
+		{"postgis geometry", "USER-DEFINED", "geometry", "geometry(Point,4326)", "geometry(Point,4326)"},
+		{"postgis geography", "USER-DEFINED", "geography", "geography(Point,4326)", "geography(Point,4326)"},
+		{"postgis geometry without modifier", "USER-DEFINED", "geometry", "geometry", "geometry"},
+		{"pgvector halfvec", "USER-DEFINED", "halfvec", "halfvec(768)", "halfvec(768)"},
+		{"postgis geometry array", "ARRAY", "_geometry", "geometry(Point,4326)[]", "geometry(Point,4326)[]"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := reader.mapDataType(tt.pgType, tt.udtName, tt.formattedType, false); got != tt.want {
+				t.Errorf("mapDataType() = %q, want %q", got, tt.want)
+			}
+		})
+	}
+}

pkg/writers/pgsql/README.md

@@ -171,6 +171,7 @@ When `include_audit` is enabled, adds:
 - Function-based indexes
 - Concurrent index creation (`CREATE INDEX CONCURRENTLY`) via `Index.Concurrent`
 - Check constraints with expressions
+- Extension types and indexes: PostGIS, pgvector, citext, hstore, ltree (see below)
 
 ## Data Types
 
@@ -186,6 +187,108 @@ Supports all PostgreSQL data types:
 - Network: INET, CIDR, MACADDR
 - Special: ARRAY, HSTORE
 
+## Extension Types (PostGIS, pgvector)
+
+Extension column types are preserved verbatim, including their type modifier:
+
+| Type | Example column type | Extension |
+|------|---------------------|-----------|
+| PostGIS | `geometry(Point,4326)`, `geography(Point)`, `box2d`, `raster` | `postgis`, `postgis_raster`, `postgis_topology` |
+| pgvector | `vector(1536)`, `halfvec(768)`, `sparsevec(1000)` | `vector` |
+| Other | `citext`, `hstore`, `ltree` | `citext`, `hstore`, `ltree` |
+
+`CREATE EXTENSION IF NOT EXISTS <ext>;` is emitted automatically for every extension the
+schema needs. See [Extensions](#extensions).
+
+### Extension Indexes
+
+`Index.Type` selects the access method: `gist`, `spgist`, `brin` (PostGIS), `hnsw`, `ivfflat`
+(pgvector), `vchordrq`, `vchordg` (VectorChord), `bm25` (pg_search).
+
+Operator class and access-method parameters ride in `Index.Comment`:
+
+```
+opclass=vector_l2_ops; with (lists=100)
+```
+
+- `opclass=<name>` — used only when compatible with the column type; otherwise ignored.
+  Bare operator class names in the comment (e.g. `gin_trgm_ops`) are also recognized.
+- `with (k=v, …)` — rendered as `WITH (k = v, …)`. Only well-formed `key = value` pairs are
+  kept, so comment prose never reaches the DDL. Values may be bare (`lists=100`), quoted
+  (`key_field='id'`), or dollar-quoted (`options=$$[build.internal]$$`).
+
+Defaults when no operator class is requested:
+
+| Access method | Column type | Emitted operator class |
+|---------------|-------------|------------------------|
+| `hnsw`, `ivfflat`, `vchordrq`, `vchordg` | `vector` / `halfvec` / `sparsevec` / `bit` | `vector_cosine_ops` / `halfvec_cosine_ops` / `sparsevec_cosine_ops` / `bit_hamming_ops` |
+| `gist`, `spgist`, `brin` | `geometry`, `geography` | none (PostGIS default operator class) |
+| `gin` | text / `jsonb` / array | `gin_trgm_ops` / `jsonb_ops` / `array_ops` |
+
+pgvector defines no default operator class, so a vector index always names one.
+
+```sql
+CREATE INDEX IF NOT EXISTS idx_documents_embedding
+  ON public.documents USING ivfflat (embedding vector_cosine_ops) WITH (lists = 100);
+CREATE INDEX IF NOT EXISTS idx_documents_location
+  ON public.documents USING gist (location);
+```
+
+Migrations only recreate an index when both sides specify a hint and they differ, so a model
+without hints does not churn against a live database.
+
+## Extensions
+
+`CREATE EXTENSION IF NOT EXISTS <ext>;` is emitted per schema, deduplicated and ordered so
+dependencies come first (`postgis` before `postgis_topology`/`postgis_raster`/`pgrouting`,
+`vector` before `vchord`). Names needing quoting are quoted: `CREATE EXTENSION IF NOT EXISTS "uuid-ossp";`
+
+### Detection
+
+| Source | Example | Extension |
+|--------|---------|-----------|
+| Column type | `vector(1536)`, `geometry(Point,4326)`, `citext`, `ltree` | `vector`, `postgis`, `citext`, `ltree` |
+| Index access method | `hnsw`, `ivfflat` / `vchordrq`, `vchordg` / `bm25` | `vector` / `vchord` / `pg_search` |
+| Operator class | `gin_trgm_ops`, `gist_ltree_ops` | `pg_trgm`, `ltree` |
+| GIN/GiST on a scalar type | `USING gin (views)` | `btree_gin` / `btree_gist` |
+| Function in a default, CHECK, index `WHERE`, or view body | `uuid_generate_v4()`, `crypt()`, `ST_Area()`, `unaccent()`, `json_matches_schema()` | `uuid-ossp`, `pgcrypto`, `postgis`, `unaccent`, `pg_jsonschema` |
+
+`gen_random_uuid()` is built in since PostgreSQL 13 and does not pull in `pgcrypto`.
+
+### Declaring extensions explicitly
+
+Extensions that leave no trace in the schema go in `schema.Metadata["extensions"]`, as a list
+or a comma-separated string. Dependencies are pulled in automatically; unknown names are kept
+as given. The PostgreSQL reader populates this from `pg_extension` for the schemas it reads.
+
+```yaml
+metadata:
+  extensions: [pg_cron, timescaledb, pg_stat_statements]
+```
+
+### Recognized extensions
+
+| Category | Extensions |
+|----------|------------|
+| ai/search | `vector`, `vchord` |
+| document | `hstore`, `ltree` |
+| federation | `postgres_fdw` |
+| geospatial | `postgis`, `postgis_raster`, `postgis_topology`, `pgrouting` |
+| indexing | `btree_gin`, `btree_gist` |
+| integration | `http` |
+| integrity | `amcheck` |
+| jobs / scheduling | `pg_background`, `pg_cron` |
+| maintenance | `pg_repack`, `pgstattuple` |
+| observability | `pg_qualstats`, `pg_stat_statements` |
+| partitioning | `pg_partman` |
+| procedural | `plpython3u` |
+| search | `pg_search`, `pg_textsearch` |
+| security | `pgcrypto` |
+| text | `citext`, `fuzzystrmatch`, `pg_trgm`, `unaccent` |
+| time-series | `timescaledb` |
+| utility | `uuid-ossp` |
+| validation | `pg_jsonschema` |
+
 ## Notes
 
 - Generated SQL is formatted and readable

pkg/writers/pgsql/extensions_test.go

@@ -0,0 +1,260 @@
+package pgsql
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+
+	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/writers"
+)
+
+// buildExtensionSchema returns a single-table schema the extension detection tests mutate.
+func buildExtensionSchema(t *testing.T) (*models.Schema, *models.Table) {
+	t.Helper()
+
+	schema := models.InitSchema("public")
+	table := models.InitTable("documents", "public")
+	schema.Tables = append(schema.Tables, table)
+	return schema, table
+}
+
+func addColumn(table *models.Table, name, sqlType string) *models.Column {
+	col := models.InitColumn(name, table.Name, table.Schema)
+	col.Type = sqlType
+	table.Columns[name] = col
+	return col
+}
+
+func TestRequiredExtensions_Detection(t *testing.T) {
+	tests := []struct {
+		name  string
+		build func(schema *models.Schema, table *models.Table)
+		want  []string
+	}{
+		{
+			name:  "no extensions",
+			build: func(_ *models.Schema, table *models.Table) { addColumn(table, "id", "integer") },
+			want:  nil,
+		},
+		{
+			name: "column type",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "embedding", "vector(1536)")
+				addColumn(table, "name", "citext")
+			},
+			want: []string{"citext", "vector"},
+		},
+		{
+			name: "column default function",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "id", "uuid").Default = "uuid_generate_v4()"
+			},
+			want: []string{"uuid-ossp"},
+		},
+		{
+			name: "check constraint expression",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "geom", "geometry")
+				table.Constraints["chk_geom"] = &models.Constraint{
+					Name:       "chk_geom",
+					Type:       models.CheckConstraint,
+					Expression: "ST_IsValid(geom)",
+				}
+			},
+			want: []string{"postgis"},
+		},
+		{
+			name: "partial index predicate",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "title", "text")
+				table.Indexes["idx_title"] = &models.Index{
+					Name:    "idx_title",
+					Type:    "btree",
+					Columns: []string{"title"},
+					Where:   "similarity(title, 'x') > 0.3",
+				}
+			},
+			want: []string{"pg_trgm"},
+		},
+		{
+			name: "view definition",
+			build: func(schema *models.Schema, table *models.Table) {
+				addColumn(table, "title", "text")
+				schema.Views = append(schema.Views, &models.View{
+					Name:       "v_documents",
+					Schema:     "public",
+					Definition: "SELECT unaccent(title) FROM documents",
+				})
+			},
+			want: []string{"unaccent"},
+		},
+		{
+			name: "index access method",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "body", "text")
+				table.Indexes["idx_body"] = &models.Index{
+					Name:    "idx_body",
+					Type:    "bm25",
+					Columns: []string{"body"},
+					Comment: "with (key_field='id')",
+				}
+			},
+			want: []string{"pg_search"},
+		},
+		{
+			name: "vchord depends on vector",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "embedding", "vector(3)")
+				table.Indexes["idx_embedding"] = &models.Index{
+					Name:    "idx_embedding",
+					Type:    "vchordrq",
+					Columns: []string{"embedding"},
+				}
+			},
+			want: []string{"vector", "vchord"},
+		},
+		{
+			name: "gin on scalar needs btree_gin",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "views", "integer")
+				table.Indexes["idx_views"] = &models.Index{
+					Name:    "idx_views",
+					Type:    "gin",
+					Columns: []string{"views"},
+				}
+			},
+			want: []string{"btree_gin"},
+		},
+		{
+			name: "gist on scalar needs btree_gist",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "views", "integer")
+				table.Indexes["idx_views"] = &models.Index{
+					Name:    "idx_views",
+					Type:    "gist",
+					Columns: []string{"views"},
+				}
+			},
+			want: []string{"btree_gist"},
+		},
+		{
+			name: "gist on geometry uses postgis operator classes",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "location", "geometry(Point,4326)")
+				table.Indexes["idx_location"] = &models.Index{
+					Name:    "idx_location",
+					Type:    "gist",
+					Columns: []string{"location"},
+				}
+			},
+			want: []string{"postgis"},
+		},
+		{
+			name: "gin on jsonb needs no companion",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "payload", "jsonb")
+				table.Indexes["idx_payload"] = &models.Index{
+					Name:    "idx_payload",
+					Type:    "gin",
+					Columns: []string{"payload"},
+				}
+			},
+			want: nil,
+		},
+		{
+			name: "gin on text uses pg_trgm",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "title", "text")
+				table.Indexes["idx_title"] = &models.Index{
+					Name:    "idx_title",
+					Type:    "gin",
+					Columns: []string{"title"},
+				}
+			},
+			want: []string{"pg_trgm"},
+		},
+		{
+			name: "gin on array needs no companion",
+			build: func(_ *models.Schema, table *models.Table) {
+				addColumn(table, "tags", "text[]")
+				table.Indexes["idx_tags"] = &models.Index{
+					Name:    "idx_tags",
+					Type:    "gin",
+					Columns: []string{"tags"},
+				}
+			},
+			want: nil,
+		},
+		{
+			name: "declared in metadata as string",
+			build: func(schema *models.Schema, _ *models.Table) {
+				schema.Metadata = map[string]any{"extensions": "pg_cron, timescaledb"}
+			},
+			want: []string{"pg_cron", "timescaledb"},
+		},
+		{
+			name: "declared in metadata as list",
+			build: func(schema *models.Schema, _ *models.Table) {
+				schema.Metadata = map[string]any{"extensions": []any{"postgis_topology", "pg_stat_statements"}}
+			},
+			// postgis is pulled in as a dependency of postgis_topology and emitted first.
+			want: []string{"pg_stat_statements", "postgis", "postgis_topology"},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			schema, table := buildExtensionSchema(t)
+			tt.build(schema, table)
+
+			if got := requiredExtensions(schema); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("requiredExtensions() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestRequiredExtensions_NilSchema(t *testing.T) {
+	if got := requiredExtensions(nil); got != nil {
+		t.Errorf("requiredExtensions(nil) = %v, want nil", got)
+	}
+}
+
+func TestWriteDatabase_QuotesExtensionNames(t *testing.T) {
+	db := models.InitDatabase("testdb")
+	schema, table := buildExtensionSchema(t)
+	addColumn(table, "id", "uuid").Default = "uuid_generate_v4()"
+	db.Schemas = append(db.Schemas, schema)
+
+	output := writeDatabaseOutput(t, db)
+	if !strings.Contains(output, `CREATE EXTENSION IF NOT EXISTS "uuid-ossp";`) {
+		t.Fatalf("expected quoted extension name, got:\n%s", output)
+	}
+}
+
+func TestGenerateSchemaStatements_ExtensionDependencyOrder(t *testing.T) {
+	schema, table := buildExtensionSchema(t)
+	addColumn(table, "embedding", "vector(3)")
+	table.Indexes["idx_embedding"] = &models.Index{
+		Name:    "idx_embedding",
+		Type:    "vchordrq",
+		Columns: []string{"embedding"},
+	}
+
+	writer := NewWriter(&writers.WriterOptions{})
+	statements, err := writer.GenerateSchemaStatements(schema)
+	if err != nil {
+		t.Fatalf("GenerateSchemaStatements failed: %v", err)
+	}
+
+	joined := strings.Join(statements, "\n")
+	vector := strings.Index(joined, "CREATE EXTENSION IF NOT EXISTS vector")
+	vchord := strings.Index(joined, "CREATE EXTENSION IF NOT EXISTS vchord")
+	if vector < 0 || vchord < 0 {
+		t.Fatalf("expected vector and vchord extensions, got:\n%s", joined)
+	}
+	if vector > vchord {
+		t.Fatalf("expected vector to be created before vchord, got:\n%s", joined)
+	}
+}

pkg/writers/pgsql/migration_writer.go

@@ -164,14 +164,14 @@ func (w *MigrationWriter) WriteMigration(model *models.Database, current *models
 func (w *MigrationWriter) generateSchemaScripts(model *models.Schema, current *models.Schema) ([]MigrationScript, error) {
 	scripts := make([]MigrationScript, 0)
 
-	if schemaRequiresPGTrgm(model) {
+	for _, extension := range requiredExtensions(model) {
 		scripts = append(scripts, MigrationScript{
-			ObjectName: "extension.pg_trgm",
+			ObjectName: "extension." + extension,
 			ObjectType: "create extension",
 			Schema:     model.Name,
 			Priority:   80,
 			Sequence:   len(scripts),
-			Body:       "CREATE EXTENSION IF NOT EXISTS pg_trgm;",
+			Body:       fmt.Sprintf("CREATE EXTENSION IF NOT EXISTS %s;", pgsql.QuoteExtensionName(extension)),
 		})
 	}
 
@@ -646,13 +646,14 @@ func (w *MigrationWriter) generateIndexScripts(model *models.Schema, current *mo
 				}
 
 				sql, err := w.executor.ExecuteCreateIndex(CreateIndexData{
-					SchemaName: model.Name,
-					TableName:  modelTable.Name,
-					IndexName:  indexName,
-					IndexType:  indexType,
-					Columns:    strings.Join(columnExprs, ", "),
-					Unique:     modelIndex.Unique,
-					Concurrent: modelIndex.Concurrent,
+					SchemaName:        model.Name,
+					TableName:         modelTable.Name,
+					IndexName:         indexName,
+					IndexType:         indexType,
+					Columns:           strings.Join(columnExprs, ", "),
+					Unique:            modelIndex.Unique,
+					Concurrent:        modelIndex.Concurrent,
+					StorageParameters: indexStorageParameters(modelIndex.Comment),
 				})
 				if err != nil {
 					return nil, err
@@ -674,20 +675,31 @@ func (w *MigrationWriter) generateIndexScripts(model *models.Schema, current *mo
 	return scripts, nil
 }
 
+// buildIndexColumnExpressions renders the column list of an index, appending the operator
+// class each column needs for the access method (GIN opclasses, pgvector distance ops,
+// explicitly requested PostGIS opclasses). Columns that cannot be resolved on the table are
+// emitted verbatim.
 func buildIndexColumnExpressions(table *models.Table, index *models.Index, indexType string) []string {
+	return buildIndexColumnExpressionsFiltered(table, index, indexType, false)
+}
+
+// buildIndexColumnExpressionsFiltered is buildIndexColumnExpressions with the option to drop
+// columns that do not exist on the table instead of emitting them verbatim.
+func buildIndexColumnExpressionsFiltered(table *models.Table, index *models.Index, indexType string, skipUnresolved bool) []string {
 	columnExprs := make([]string, 0, len(index.Columns))
 	for _, colName := range index.Columns {
-		colExpr := colName
-		if table != nil {
-			if col, ok := resolveIndexColumn(table, colName); ok && col != nil {
-				colExpr = col.SQLName()
-				if strings.EqualFold(indexType, "gin") {
-					opClass := ginOperatorClassForColumn(col, index.Comment)
-					if opClass != "" {
-						colExpr = fmt.Sprintf("%s %s", col.SQLName(), opClass)
-					}
-				}
+		col, ok := resolveIndexColumn(table, colName)
+		if !ok || col == nil {
+			if skipUnresolved {
+				continue
 			}
+			columnExprs = append(columnExprs, colName)
+			continue
+		}
+
+		colExpr := col.SQLName()
+		if opClass := indexOperatorClassForColumn(col, indexType, index.Comment); opClass != "" {
+			colExpr = fmt.Sprintf("%s %s", colExpr, opClass)
 		}
 		columnExprs = append(columnExprs, colExpr)
 	}
@@ -1046,5 +1058,19 @@ func indexesEqual(idx1, idx2 *models.Index) bool {
 			return false
 		}
 	}
-	return true
+	// Operator class and storage parameters ride along in the index comment. They only
+	// signal a difference when both sides specify one, so an index whose model side omits
+	// the hint is not recreated on every migration.
+	if !indexHintsEqual(extractOperatorClass(idx1.Comment), extractOperatorClass(idx2.Comment)) {
+		return false
+	}
+	return indexHintsEqual(indexStorageParameters(idx1.Comment), indexStorageParameters(idx2.Comment))
+}
+
+// indexHintsEqual compares two optional index hints, treating an unspecified hint as a match.
+func indexHintsEqual(hint1, hint2 string) bool {
+	if hint1 == "" || hint2 == "" {
+		return true
+	}
+	return strings.EqualFold(hint1, hint2)
 }

pkg/writers/pgsql/migration_writer_test.go

@@ -852,3 +852,93 @@ func TestWriteMigration_NilCurrentTreatsDatabaseAsEmpty(t *testing.T) {
 		t.Fatalf("expected CREATE TABLE in migration output, got:\n%s", output)
 	}
 }
+
+func TestWriteMigration_VectorAndPostGISIndexes(t *testing.T) {
+	current := models.InitDatabase("testdb")
+	current.Schemas = append(current.Schemas, models.InitSchema("public"))
+
+	model := models.InitDatabase("testdb")
+	modelSchema := models.InitSchema("public")
+
+	table := models.InitTable("documents", "public")
+
+	embedding := models.InitColumn("embedding", "documents", "public")
+	embedding.Type = "vector(1536)"
+	table.Columns["embedding"] = embedding
+
+	location := models.InitColumn("location", "documents", "public")
+	location.Type = "geometry(Point,4326)"
+	table.Columns["location"] = location
+
+	table.Indexes["idx_documents_embedding"] = &models.Index{
+		Name:    "idx_documents_embedding",
+		Type:    "ivfflat",
+		Columns: []string{"embedding"},
+		Comment: "opclass=vector_cosine_ops; with (lists=100)",
+	}
+	table.Indexes["idx_documents_location"] = &models.Index{
+		Name:    "idx_documents_location",
+		Type:    "gist",
+		Columns: []string{"location"},
+	}
+
+	modelSchema.Tables = append(modelSchema.Tables, table)
+	model.Schemas = append(model.Schemas, modelSchema)
+
+	var buf bytes.Buffer
+	writer, err := NewMigrationWriter(&writers.WriterOptions{})
+	if err != nil {
+		t.Fatalf("Failed to create writer: %v", err)
+	}
+	writer.writer = &buf
+
+	if err := writer.WriteMigration(model, current); err != nil {
+		t.Fatalf("WriteMigration failed: %v", err)
+	}
+
+	output := buf.String()
+	for _, want := range []string{
+		"CREATE EXTENSION IF NOT EXISTS postgis;",
+		"CREATE EXTENSION IF NOT EXISTS vector;",
+		"vector(1536)",
+		"geometry(Point,4326)",
+		"USING ivfflat (embedding vector_cosine_ops) WITH (lists = 100)",
+		"USING gist (location)",
+	} {
+		if !strings.Contains(output, want) {
+			t.Fatalf("expected migration to contain %q, got:\n%s", want, output)
+		}
+	}
+}
+
+func TestIndexesEqual_OperatorClassAndStorageParameters(t *testing.T) {
+	newIndex := func(comment string) *models.Index {
+		return &models.Index{
+			Name:    "idx_documents_embedding",
+			Type:    "hnsw",
+			Columns: []string{"embedding"},
+			Comment: comment,
+		}
+	}
+
+	tests := []struct {
+		name      string
+		comment1  string
+		comment2  string
+		wantEqual bool
+	}{
+		{"identical hints", "opclass=vector_l2_ops", "opclass=vector_l2_ops", true},
+		{"different operator class", "opclass=vector_l2_ops", "opclass=vector_cosine_ops", false},
+		{"different storage parameters", "with (m=16)", "with (m=32)", false},
+		{"unspecified hint on one side", "", "opclass=vector_l2_ops; with (m=16)", true},
+		{"unrelated comments", "primary lookup index", "primary lookup index", true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := indexesEqual(newIndex(tt.comment1), newIndex(tt.comment2)); got != tt.wantEqual {
+				t.Errorf("indexesEqual() = %v, want %v", got, tt.wantEqual)
+			}
+		})
+	}
+}

pkg/writers/pgsql/templates.go

@@ -140,6 +140,9 @@ type CreateIndexData struct {
 	Columns    string
 	Unique     bool
 	Concurrent bool
+	// StorageParameters holds access-method parameters rendered as WITH (...),
+	// e.g. "lists = 100" for ivfflat or "m = 16, ef_construction = 64" for hnsw.
+	StorageParameters string
 }
 
 // CreateForeignKeyData contains data for create foreign key template

pkg/writers/pgsql/templates/create_index.tmpl

@@ -1,2 +1,2 @@
 CREATE {{if .Unique}}UNIQUE {{end}}INDEX {{if .Concurrent}}CONCURRENTLY {{end}}IF NOT EXISTS {{quote_ident .IndexName}}
-  ON {{qual_table .SchemaName .TableName}} USING {{.IndexType}} ({{.Columns}});
+  ON {{qual_table .SchemaName .TableName}} USING {{.IndexType}} ({{.Columns}}){{if .StorageParameters}} WITH ({{.StorageParameters}}){{end}};

pkg/writers/pgsql/writer.go

@@ -6,8 +6,10 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"regexp"
 	"sort"
 	"strings"
+	"sync"
 	"time"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
@@ -147,8 +149,8 @@ func (w *Writer) GenerateSchemaStatements(schema *models.Schema) ([]string, erro
 		statements = append(statements, fmt.Sprintf("CREATE SCHEMA IF NOT EXISTS %s", schema.SQLName()))
 	}
 
-	if schemaRequiresPGTrgm(schema) {
-		statements = append(statements, `CREATE EXTENSION IF NOT EXISTS pg_trgm`)
+	for _, extension := range requiredExtensions(schema) {
+		statements = append(statements, fmt.Sprintf("CREATE EXTENSION IF NOT EXISTS %s", pgsql.QuoteExtensionName(extension)))
 	}
 
 	// Phase 2: Create sequences
@@ -271,18 +273,12 @@ func (w *Writer) GenerateSchemaStatements(schema *models.Schema) ([]string, erro
 				indexType = "btree"
 			}
 
-			// Build column expressions with operator class support for GIN indexes
-			columnExprs := make([]string, 0, len(index.Columns))
-			for _, colName := range index.Columns {
-				colExpr := colName
-				if col, ok := resolveIndexColumn(table, colName); ok {
-					if strings.EqualFold(indexType, "gin") {
-						if opClass := ginOperatorClassForColumn(col, index.Comment); opClass != "" {
-							colExpr = fmt.Sprintf("%s %s", colName, opClass)
-						}
-					}
-				}
-				columnExprs = append(columnExprs, colExpr)
+			// Build column expressions with operator class support (GIN, pgvector, PostGIS)
+			columnExprs := buildIndexColumnExpressions(table, index, indexType)
+
+			withClause := ""
+			if params := indexStorageParameters(index.Comment); params != "" {
+				withClause = fmt.Sprintf(" WITH (%s)", params)
 			}
 
 			whereClause := ""
@@ -290,8 +286,8 @@ func (w *Writer) GenerateSchemaStatements(schema *models.Schema) ([]string, erro
 				whereClause = fmt.Sprintf(" WHERE %s", index.Where)
 			}
 
-			stmt := fmt.Sprintf("CREATE %sINDEX IF NOT EXISTS %s ON %s USING %s (%s)%s",
-				uniqueStr, quoteIdentifier(index.Name), w.qualTable(schema.SQLName(), table.SQLName()), indexType, strings.Join(columnExprs, ", "), whereClause)
+			stmt := fmt.Sprintf("CREATE %sINDEX IF NOT EXISTS %s ON %s USING %s (%s)%s%s",
+				uniqueStr, quoteIdentifier(index.Name), w.qualTable(schema.SQLName(), table.SQLName()), indexType, strings.Join(columnExprs, ", "), withClause, whereClause)
 			statements = append(statements, stmt)
 		}
 	}
@@ -819,11 +815,14 @@ func (w *Writer) writeCreateSchema(schema *models.Schema) error {
 }
 
 func (w *Writer) writeRequiredExtensions(schema *models.Schema) error {
-	if !schemaRequiresPGTrgm(schema) {
+	extensions := requiredExtensions(schema)
+	if len(extensions) == 0 {
 		return nil
 	}
 
-	fmt.Fprintln(w.writer, "CREATE EXTENSION IF NOT EXISTS pg_trgm;")
+	for _, extension := range extensions {
+		fmt.Fprintf(w.writer, "CREATE EXTENSION IF NOT EXISTS %s;\n", pgsql.QuoteExtensionName(extension))
+	}
 	fmt.Fprintln(w.writer)
 	return nil
 }
@@ -1063,21 +1062,13 @@ func (w *Writer) writeIndexes(schema *models.Schema) error {
 				indexName = fmt.Sprintf("%s_%s_%s", indexType, table.SQLName(), strings.ToLower(columnSuffix))
 			}
 
-			// Build column list with operator class support for GIN indexes
-			columnExprs := make([]string, 0, len(index.Columns))
-			for _, colName := range index.Columns {
-				if col, ok := resolveIndexColumn(table, colName); ok {
-					colExpr := col.SQLName()
-					if strings.EqualFold(index.Type, "gin") {
-						opClass := ginOperatorClassForColumn(col, index.Comment)
-						if opClass != "" {
-							colExpr = fmt.Sprintf("%s %s", col.SQLName(), opClass)
-						}
-					}
-					columnExprs = append(columnExprs, colExpr)
-				}
+			indexType := index.Type
+			if indexType == "" {
+				indexType = "btree"
 			}
 
+			// Build column list with operator class support (GIN, pgvector, PostGIS)
+			columnExprs := buildIndexColumnExpressionsFiltered(table, index, indexType, true)
 			if len(columnExprs) == 0 {
 				continue
 			}
@@ -1087,9 +1078,9 @@ func (w *Writer) writeIndexes(schema *models.Schema) error {
 				unique = "UNIQUE "
 			}
 
-			indexType := index.Type
-			if indexType == "" {
-				indexType = "btree"
+			withClause := ""
+			if params := indexStorageParameters(index.Comment); params != "" {
+				withClause = fmt.Sprintf(" WITH (%s)", params)
 			}
 
 			whereClause := ""
@@ -1104,8 +1095,8 @@ func (w *Writer) writeIndexes(schema *models.Schema) error {
 
 			fmt.Fprintf(w.writer, "CREATE %sINDEX %sIF NOT EXISTS %s\n",
 				unique, concurrently, indexName)
-			fmt.Fprintf(w.writer, "  ON %s USING %s (%s)%s;\n\n",
-				w.qualTable(schema.SQLName(), table.SQLName()), indexType, strings.Join(columnExprs, ", "), whereClause)
+			fmt.Fprintf(w.writer, "  ON %s USING %s (%s)%s%s;\n\n",
+				w.qualTable(schema.SQLName(), table.SQLName()), indexType, strings.Join(columnExprs, ", "), withClause, whereClause)
 		}
 	}
 
@@ -1483,7 +1474,69 @@ func isTextTypeWithoutLength(colType string) bool {
 	return strings.EqualFold(colType, "text")
 }
 
-func ginOperatorClassForColumn(col *models.Column, comment string) string {
+// vectorOperatorClasses maps pgvector operator classes to the column base type they
+// apply to. pgvector defines no default operator class, so an hnsw/ivfflat index must
+// always name one explicitly.
+var vectorOperatorClasses = map[string]string{
+	"vector_l2_ops":        "vector",
+	"vector_ip_ops":        "vector",
+	"vector_cosine_ops":    "vector",
+	"vector_l1_ops":        "vector",
+	"halfvec_l2_ops":       "halfvec",
+	"halfvec_ip_ops":       "halfvec",
+	"halfvec_cosine_ops":   "halfvec",
+	"halfvec_l1_ops":       "halfvec",
+	"sparsevec_l2_ops":     "sparsevec",
+	"sparsevec_ip_ops":     "sparsevec",
+	"sparsevec_cosine_ops": "sparsevec",
+	"sparsevec_l1_ops":     "sparsevec",
+	"bit_hamming_ops":      "bit",
+	"bit_jaccard_ops":      "bit",
+}
+
+// defaultVectorOperatorClasses is the operator class used for an hnsw/ivfflat index when
+// the index comment does not request one. Cosine distance is the common default for
+// embedding columns; override it with an "opclass" hint in the index comment.
+var defaultVectorOperatorClasses = map[string]string{
+	"vector":    "vector_cosine_ops",
+	"halfvec":   "halfvec_cosine_ops",
+	"sparsevec": "sparsevec_cosine_ops",
+	"bit":       "bit_hamming_ops",
+}
+
+// spatialOperatorClasses are the PostGIS operator classes recognized in index comments.
+// PostGIS installs default operator classes for gist/spgist/brin, so these are only
+// emitted when explicitly requested (e.g. the 3D/nD variants).
+var spatialOperatorClasses = map[string]bool{
+	"gist_geometry_ops_2d":            true,
+	"gist_geometry_ops_nd":            true,
+	"gist_geography_ops":              true,
+	"spgist_geometry_ops_2d":          true,
+	"spgist_geometry_ops_3d":          true,
+	"spgist_geometry_ops_nd":          true,
+	"brin_geometry_inclusion_ops_2d":  true,
+	"brin_geometry_inclusion_ops_3d":  true,
+	"brin_geometry_inclusion_ops_4d":  true,
+	"brin_geography_inclusion_ops_2d": true,
+	"btree_geometry_ops":              true,
+	"btree_geography_ops":             true,
+}
+
+// isVectorIndexMethod reports whether the access method indexes pgvector types, which
+// covers both pgvector itself (hnsw, ivfflat) and VectorChord (vchordrq, vchordg).
+func isVectorIndexMethod(method string) bool {
+	switch strings.ToLower(strings.TrimSpace(method)) {
+	case "hnsw", "ivfflat", "vchordrq", "vchordg":
+		return true
+	default:
+		return false
+	}
+}
+
+// indexOperatorClassForColumn returns the operator class to emit for a column in an index
+// of the given access method, honouring an explicit request from the index comment when it
+// is compatible with the column type.
+func indexOperatorClassForColumn(col *models.Column, indexType, comment string) string {
 	if col == nil {
 		return ""
 	}
@@ -1492,26 +1545,53 @@ func ginOperatorClassForColumn(col *models.Column, comment string) string {
 	baseType := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
 	isArray := pgsql.IsArrayType(sqlType)
 	requested := extractOperatorClass(comment)
-
-	if requested != "" && ginOperatorClassCompatible(baseType, isArray, requested) {
-		return requested
+	method := strings.ToLower(strings.TrimSpace(indexType))
+	if method == "" {
+		method = "btree"
 	}
 
-	if isArray {
-		return "array_ops"
+	if requested != "" && operatorClassCompatible(method, baseType, isArray, requested) {
+		return requested
 	}
 
 	switch {
-	case isTextGinBaseType(baseType):
-		return "gin_trgm_ops"
-	case baseType == "jsonb":
-		return "jsonb_ops"
+	case method == "gin":
+		if isArray {
+			return "array_ops"
+		}
+		switch {
+		case isTextGinBaseType(baseType):
+			return "gin_trgm_ops"
+		case baseType == "jsonb":
+			return "jsonb_ops"
+		default:
+			return requested
+		}
+	case isVectorIndexMethod(method):
+		if isArray {
+			return ""
+		}
+		return defaultVectorOperatorClasses[baseType]
 	default:
-		return requested
+		// gist/spgist/brin/btree have default operator classes (PostGIS included),
+		// so nothing is emitted unless the comment requested a compatible class.
+		return ""
 	}
 }
 
-func ginOperatorClassCompatible(baseType string, isArray bool, opClass string) bool {
+// ginOperatorClassForColumn is the GIN-specific form of indexOperatorClassForColumn.
+func ginOperatorClassForColumn(col *models.Column, comment string) string {
+	return indexOperatorClassForColumn(col, "gin", comment)
+}
+
+func operatorClassCompatible(method, baseType string, isArray bool, opClass string) bool {
+	if vectorType, ok := vectorOperatorClasses[opClass]; ok {
+		return !isArray && baseType == vectorType && isVectorIndexMethod(method)
+	}
+	if spatialOperatorClasses[opClass] {
+		return !isArray && pgsql.IsSpatialType(baseType)
+	}
+
 	switch opClass {
 	case "gin_trgm_ops", "gin_bigm_ops":
 		return !isArray && isTextGinBaseType(baseType)
@@ -1524,6 +1604,10 @@ func ginOperatorClassCompatible(baseType string, isArray bool, opClass string) b
 	}
 }
 
+func ginOperatorClassCompatible(baseType string, isArray bool, opClass string) bool {
+	return operatorClassCompatible("gin", baseType, isArray, opClass)
+}
+
 func isTextGinBaseType(baseType string) bool {
 	switch baseType {
 	case "text", "varchar", "character varying", "char", "character", "string", "citext", "bpchar":
@@ -1533,29 +1617,188 @@ func isTextGinBaseType(baseType string) bool {
 	}
 }
 
-func schemaRequiresPGTrgm(schema *models.Schema) bool {
+// requiredExtensions returns the PostgreSQL extensions a schema depends on, ordered so
+// that dependencies are created first (postgis before postgis_topology, vector before
+// vchord). Extensions are detected from column types, index access methods, resolved
+// operator classes, and function calls in defaults, check constraints, partial index
+// predicates and view definitions. Extensions that leave no trace in the model (pg_cron,
+// timescaledb, postgres_fdw, …) can be declared in schema.Metadata["extensions"].
+func requiredExtensions(schema *models.Schema) []string {
 	if schema == nil {
-		return false
+		return nil
 	}
+
+	required := make(map[string]bool)
+	add := func(names ...string) {
+		for _, name := range names {
+			if name != "" {
+				required[name] = true
+			}
+		}
+	}
+
+	add(declaredExtensions(schema)...)
+
+	for _, view := range schema.Views {
+		if view == nil {
+			continue
+		}
+		add(pgsql.ExtensionsForExpression(view.Definition)...)
+	}
+
 	for _, table := range schema.Tables {
 		if table == nil {
 			continue
 		}
-		for _, index := range table.Indexes {
-			if index == nil || !strings.EqualFold(index.Type, "gin") {
+
+		for _, col := range table.Columns {
+			if col == nil {
 				continue
 			}
+			add(pgsql.TypeExtension(effectiveColumnSQLType(col)))
+			if def, ok := col.Default.(string); ok {
+				add(pgsql.ExtensionsForExpression(def)...)
+			}
+		}
+
+		for _, constraint := range table.Constraints {
+			if constraint == nil {
+				continue
+			}
+			add(pgsql.ExtensionsForExpression(constraint.Expression)...)
+		}
+
+		for _, index := range table.Indexes {
+			if index == nil {
+				continue
+			}
+			add(pgsql.IndexMethodExtension(index.Type))
+			add(pgsql.ExtensionsForExpression(index.Where)...)
+
 			for _, colName := range index.Columns {
 				col, ok := resolveIndexColumn(table, colName)
 				if !ok || col == nil {
 					continue
 				}
-				if ginOperatorClassForColumn(col, index.Comment) == "gin_trgm_ops" {
-					return true
-				}
+				opClass := indexOperatorClassForColumn(col, index.Type, index.Comment)
+				add(pgsql.OperatorClassExtension(opClass))
+				add(btreeCompanionExtension(index.Type, col, opClass))
 			}
 		}
 	}
+
+	extensions := make([]string, 0, len(required))
+	for ext := range required {
+		extensions = append(extensions, ext)
+	}
+
+	// Pull in dependencies, so a declared postgis_topology also creates postgis.
+	for i := 0; i < len(extensions); i++ {
+		for _, dependency := range pgsql.ExtensionDependencies(extensions[i]) {
+			if !required[dependency] {
+				required[dependency] = true
+				extensions = append(extensions, dependency)
+			}
+		}
+	}
+
+	return pgsql.SortExtensions(extensions)
+}
+
+// declaredExtensions reads schema.Metadata["extensions"], which accepts either a list or a
+// comma-separated string. Unknown names are kept: the metadata is an explicit instruction.
+func declaredExtensions(schema *models.Schema) []string {
+	value, ok := schema.Metadata["extensions"]
+	if !ok {
+		return nil
+	}
+
+	var names []string
+	switch declared := value.(type) {
+	case string:
+		names = strings.Split(declared, ",")
+	case []string:
+		names = declared
+	case []any:
+		for _, item := range declared {
+			if name, ok := item.(string); ok {
+				names = append(names, name)
+			}
+		}
+	default:
+		return nil
+	}
+
+	cleaned := make([]string, 0, len(names))
+	for _, name := range names {
+		if name = strings.TrimSpace(name); name != "" {
+			cleaned = append(cleaned, name)
+		}
+	}
+	return cleaned
+}
+
+// btreeCompanionExtension returns btree_gin or btree_gist when a GIN/GiST index covers a
+// scalar type that neither access method has a built-in operator class for. Without the
+// companion extension PostgreSQL rejects the CREATE INDEX outright.
+func btreeCompanionExtension(indexType string, col *models.Column, opClass string) string {
+	if opClass != "" {
+		return ""
+	}
+
+	method := strings.ToLower(strings.TrimSpace(indexType))
+	if method != "gin" && method != "gist" {
+		return ""
+	}
+
+	sqlType := effectiveColumnSQLType(col)
+	if pgsql.IsArrayType(sqlType) {
+		return ""
+	}
+
+	baseType := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
+	if pgsql.TypeExtension(baseType) != "" {
+		// Extension types (geometry, vector, citext, …) ship their own operator classes.
+		return ""
+	}
+
+	if method == "gin" {
+		if nativeGinBaseType(baseType) {
+			return ""
+		}
+		return "btree_gin"
+	}
+	if nativeGistBaseType(baseType) {
+		return ""
+	}
+	return "btree_gist"
+}
+
+// nativeGinBaseType reports whether core PostgreSQL provides a GIN operator class.
+func nativeGinBaseType(baseType string) bool {
+	switch baseType {
+	case "jsonb", "json", "tsvector", "tsquery":
+		return true
+	default:
+		return false
+	}
+}
+
+// nativeGistBaseType reports whether core PostgreSQL provides a GiST operator class.
+func nativeGistBaseType(baseType string) bool {
+	switch baseType {
+	case "tsvector", "tsquery", "point", "box", "circle", "polygon", "line", "lseg", "path", "inet", "cidr":
+		return true
+	}
+	return strings.HasSuffix(baseType, "range") || strings.HasSuffix(baseType, "multirange")
+}
+
+func schemaRequiresPGTrgm(schema *models.Schema) bool {
+	for _, ext := range requiredExtensions(schema) {
+		if ext == "pg_trgm" {
+			return true
+		}
+	}
 	return false
 }
 
@@ -1642,14 +1885,21 @@ func formatStringList(items []string) string {
 
 // extractOperatorClass extracts operator class from index comment/note
 // Looks for common operator classes like gin_trgm_ops, gist_trgm_ops, etc.
+// explicitOperatorClassPattern matches an "opclass=<name>" hint, the form the PostgreSQL
+// reader uses to carry an index's operator class through the model.
+var explicitOperatorClassPattern = regexp.MustCompile(`(?i)\bopclass\s*=\s*([a-z_][a-z0-9_]*)\b`)
+
 func extractOperatorClass(comment string) string {
 	if comment == "" {
 		return ""
 	}
+
 	lowerComment := strings.ToLower(comment)
-	// Common GIN/GiST operator classes
-	opClasses := []string{"gin_trgm_ops", "gist_trgm_ops", "gin_bigm_ops", "jsonb_ops", "jsonb_path_ops", "array_ops"}
-	for _, op := range opClasses {
+	if matches := explicitOperatorClassPattern.FindStringSubmatch(lowerComment); len(matches) > 1 {
+		return matches[1]
+	}
+
+	for _, op := range knownOperatorClasses() {
 		if strings.Contains(lowerComment, op) {
 			return op
 		}
@@ -1657,6 +1907,35 @@ func extractOperatorClass(comment string) string {
 	return ""
 }
 
+// knownOperatorClasses lists every operator class recognized in an index comment,
+// longest name first so that e.g. gist_geometry_ops_nd wins over a shorter prefix.
+var knownOperatorClasses = sync.OnceValue(func() []string {
+	names := []string{"gin_trgm_ops", "gist_trgm_ops", "gin_bigm_ops", "jsonb_ops", "jsonb_path_ops", "array_ops"}
+	for name := range vectorOperatorClasses {
+		names = append(names, name)
+	}
+	for name := range spatialOperatorClasses {
+		names = append(names, name)
+	}
+	sort.Slice(names, func(i, j int) bool {
+		if len(names[i]) != len(names[j]) {
+			return len(names[i]) > len(names[j])
+		}
+		return names[i] < names[j]
+	})
+	return names
+})
+
+// indexStorageParameters extracts access-method storage parameters from an index comment.
+// Only well-formed "key = value" pairs are kept, so comment prose cannot leak into DDL.
+// Example: "opclass=vector_cosine_ops with (m=16, ef_construction=64)" -> "m = 16, ef_construction = 64".
+func indexStorageParameters(comment string) string {
+	if comment == "" {
+		return ""
+	}
+	return pgsql.FormatStorageParameters(pgsql.ExtractWithClause(comment))
+}
+
 // escapeQuote escapes single quotes in strings for SQL
 func escapeQuote(s string) string {
 	return strings.ReplaceAll(s, "'", "''")

pkg/writers/pgsql/writer_test.go

@@ -1310,3 +1310,203 @@ func TestWriteSchema_UsesStorageTypeForSerialAlterStatements(t *testing.T) {
 		t.Fatalf("expected serial alter to include USING cast, got:\n%s", output)
 	}
 }
+
+// buildVectorSpatialSchema returns a database with a pgvector column and a PostGIS column.
+func buildVectorSpatialSchema(indexType, indexComment string) *models.Database {
+	db := models.InitDatabase("testdb")
+	schema := models.InitSchema("public")
+
+	table := models.InitTable("documents", "public")
+
+	embedding := models.InitColumn("embedding", "documents", "public")
+	embedding.Type = "vector(1536)"
+	table.Columns["embedding"] = embedding
+
+	location := models.InitColumn("location", "documents", "public")
+	location.Type = "geometry(Point,4326)"
+	table.Columns["location"] = location
+
+	if indexType != "" {
+		index := &models.Index{
+			Name:    "idx_documents_embedding",
+			Type:    indexType,
+			Columns: []string{"embedding"},
+			Comment: indexComment,
+		}
+		table.Indexes[index.Name] = index
+	}
+
+	schema.Tables = append(schema.Tables, table)
+	db.Schemas = append(db.Schemas, schema)
+	return db
+}
+
+func writeDatabaseOutput(t *testing.T, db *models.Database) string {
+	t.Helper()
+
+	var buf bytes.Buffer
+	writer := NewWriter(&writers.WriterOptions{})
+	writer.writer = &buf
+
+	if err := writer.WriteDatabase(db); err != nil {
+		t.Fatalf("WriteDatabase failed: %v", err)
+	}
+	return buf.String()
+}
+
+func TestWriteDatabase_VectorAndPostGISColumnsCreateExtensions(t *testing.T) {
+	output := writeDatabaseOutput(t, buildVectorSpatialSchema("", ""))
+
+	for _, want := range []string{
+		"CREATE EXTENSION IF NOT EXISTS postgis;",
+		"CREATE EXTENSION IF NOT EXISTS vector;",
+		"vector(1536)",
+		"geometry(Point,4326)",
+	} {
+		if !strings.Contains(output, want) {
+			t.Fatalf("expected output to contain %q, got:\n%s", want, output)
+		}
+	}
+
+	// postgis must be created before postgis-dependent extensions and stay deterministic
+	if strings.Index(output, "EXISTS postgis;") > strings.Index(output, "EXISTS vector;") {
+		t.Fatalf("expected extensions to be emitted in sorted order, got:\n%s", output)
+	}
+}
+
+func TestWriteDatabase_HNSWIndexUsesDefaultVectorOperatorClass(t *testing.T) {
+	output := writeDatabaseOutput(t, buildVectorSpatialSchema("hnsw", ""))
+
+	if !strings.Contains(output, "USING hnsw (embedding vector_cosine_ops)") {
+		t.Fatalf("expected hnsw index with default vector operator class, got:\n%s", output)
+	}
+	if !strings.Contains(output, "CREATE EXTENSION IF NOT EXISTS vector;") {
+		t.Fatalf("expected pgvector extension, got:\n%s", output)
+	}
+}
+
+func TestWriteDatabase_VectorIndexHonoursRequestedOperatorClassAndStorageParameters(t *testing.T) {
+	output := writeDatabaseOutput(t, buildVectorSpatialSchema("ivfflat", "opclass=vector_l2_ops; with (lists=100)"))
+
+	if !strings.Contains(output, "USING ivfflat (embedding vector_l2_ops) WITH (lists = 100)") {
+		t.Fatalf("expected ivfflat index with requested opclass and storage parameters, got:\n%s", output)
+	}
+}
+
+func TestWriteDatabase_VectorIndexIgnoresIncompatibleOperatorClass(t *testing.T) {
+	output := writeDatabaseOutput(t, buildVectorSpatialSchema("hnsw", "opclass=halfvec_l2_ops"))
+
+	if !strings.Contains(output, "USING hnsw (embedding vector_cosine_ops)") {
+		t.Fatalf("expected halfvec operator class to be rejected for a vector column, got:\n%s", output)
+	}
+}
+
+func TestWriteDatabase_VectorIndexIgnoresCommentProseInStorageParameters(t *testing.T) {
+	output := writeDatabaseOutput(t, buildVectorSpatialSchema("hnsw", "tuned with (m=16, ef_construction=64, drop table foo)"))
+
+	if !strings.Contains(output, "WITH (m = 16, ef_construction = 64)") {
+		t.Fatalf("expected only well-formed storage parameters, got:\n%s", output)
+	}
+	if strings.Contains(output, "drop table") {
+		t.Fatalf("expected prose to be dropped from storage parameters, got:\n%s", output)
+	}
+}
+
+func TestWriteDatabase_GistIndexOnGeometryUsesDefaultOperatorClass(t *testing.T) {
+	db := models.InitDatabase("testdb")
+	schema := models.InitSchema("public")
+
+	table := models.InitTable("places", "public")
+	geom := models.InitColumn("geom", "places", "public")
+	geom.Type = "geometry(Point,4326)"
+	table.Columns["geom"] = geom
+
+	table.Indexes["idx_places_geom"] = &models.Index{
+		Name:    "idx_places_geom",
+		Type:    "gist",
+		Columns: []string{"geom"},
+	}
+
+	schema.Tables = append(schema.Tables, table)
+	db.Schemas = append(db.Schemas, schema)
+
+	output := writeDatabaseOutput(t, db)
+
+	if !strings.Contains(output, "USING gist (geom)") {
+		t.Fatalf("expected gist index to rely on the PostGIS default operator class, got:\n%s", output)
+	}
+}
+
+func TestWriteDatabase_GistIndexHonoursRequestedSpatialOperatorClass(t *testing.T) {
+	db := models.InitDatabase("testdb")
+	schema := models.InitSchema("public")
+
+	table := models.InitTable("places", "public")
+	geom := models.InitColumn("geom", "places", "public")
+	geom.Type = "geometry(PointZ,4326)"
+	table.Columns["geom"] = geom
+
+	table.Indexes["idx_places_geom_nd"] = &models.Index{
+		Name:    "idx_places_geom_nd",
+		Type:    "gist",
+		Columns: []string{"geom"},
+		Comment: "opclass=gist_geometry_ops_nd",
+	}
+
+	schema.Tables = append(schema.Tables, table)
+	db.Schemas = append(db.Schemas, schema)
+
+	output := writeDatabaseOutput(t, db)
+
+	if !strings.Contains(output, "USING gist (geom gist_geometry_ops_nd)") {
+		t.Fatalf("expected requested spatial operator class, got:\n%s", output)
+	}
+}
+
+func TestGenerateDatabaseStatements_VectorIndexIncludesOperatorClassAndParameters(t *testing.T) {
+	db := buildVectorSpatialSchema("hnsw", "opclass=vector_ip_ops; with (m=16)")
+
+	writer := NewWriter(&writers.WriterOptions{})
+	statements, err := writer.GenerateDatabaseStatements(db)
+	if err != nil {
+		t.Fatalf("GenerateDatabaseStatements failed: %v", err)
+	}
+
+	joined := strings.Join(statements, "\n")
+	for _, want := range []string{
+		"CREATE EXTENSION IF NOT EXISTS vector",
+		"CREATE EXTENSION IF NOT EXISTS postgis",
+		"USING hnsw (embedding vector_ip_ops) WITH (m = 16)",
+	} {
+		if !strings.Contains(joined, want) {
+			t.Fatalf("expected statements to contain %q, got:\n%s", want, joined)
+		}
+	}
+}
+
+func TestIndexStorageParameters(t *testing.T) {
+	tests := []struct {
+		name    string
+		comment string
+		want    string
+	}{
+		{"empty", "", ""},
+		{"no with clause", "opclass=vector_cosine_ops", ""},
+		{"single parameter", "with (lists=100)", "lists = 100"},
+		{"multiple parameters", "WITH (m = 16, ef_construction = 64)", "m = 16, ef_construction = 64"},
+		{"quoted value kept", "with (fillfactor='90')", "fillfactor = '90'"},
+		{"bm25 key field", "with (key_field='id')", "key_field = 'id'"},
+		{"dollar quoted value", "with (options = $$[build.internal]\nlists = [4096]$$)", "options = $$[build.internal]\nlists = [4096]$$"},
+		{"dollar quoted value with parens", "with (options = $$f(x)$$, m = 16)", "options = $$f(x)$$, m = 16"},
+		{"prose dropped", "with (lists=100, please drop everything)", "lists = 100"},
+		{"unterminated quote dropped", "with (key_field='id)", ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := indexStorageParameters(tt.comment); got != tt.want {
+				t.Errorf("indexStorageParameters(%q) = %q, want %q", tt.comment, got, tt.want)
+			}
+		})
+	}
+}