feat(pkg): preserve PostgreSQL types in mapDataType function

* Add support for known PostgreSQL types and modifiers
* Implement canonicalization for PostgreSQL types
* Introduce unit tests for PostgreSQL type handling

Story.md

@@ -0,0 +1,219 @@
+
+# From Scripts to RelSpec: What Years of Database Pain Taught Me
+
+It started as a need.
+A problem I’ve carried with me since my early PHP days.
+
+Every project meant doing the same work again. Same patterns, same fixes—just in a different codebase.
+It became frustrating fast.
+
+I wanted something solid. Not another workaround.
+
+## The Early Tools Phase
+
+Like most things in development, it began small.
+
+A simple PHP script.
+Then a few Python scripts.
+
+Just tools—nothing fancy. The goal was straightforward: generate code faster and remove repetitive work. I even experimented with Clarion templates at one point, trying to bend existing systems into something useful.
+
+Then came SQL scripts.
+Then PostgreSQL migration stored procedures.
+Then small Go programs using templates.
+
+Each step was solving a problem I had at the time. Nothing unified. Nothing polished. Just survival tools.
+
+---
+
+## Argitek: The First Real Attempt
+
+Eventually, those scattered ideas turned into something more structured: Argitek.
+
+Argitek powered a few real systems, including Powerbid. On paper, it sounded solid:
+
+> “Argitek Next is a powerful code generation tool designed to streamline your development workflow.”
+
+And technically, it worked.
+
+It could generate code from predefined templates, adapt to different scenarios, and reduce repetitive work. But something was off.
+
+It never felt *complete*.
+Not something I could confidently release.
+
+So I did what many developers do with almost-good-enough tools—I parked it.
+
+---
+
+## The Breaking Point: Database Migrations
+
+Over the years, one problem kept coming back:
+
+Database migrations.
+
+Not the clean, theoretical kind. The real ones.
+
+* PostgreSQL to ORM mismatches
+* DBML to SQL hacks
+* GORM inconsistencies
+* Manual fixes after “automated” migrations failed
+
+It was always messy. Always unpredictable. Always more work than expected.
+
+By 2025, after a particularly tough year, I had accumulated enough of these problems to stop ignoring them.
+
+---
+
+## December 2025: RelSpecGo Begins
+
+In December 2025, I bootstrapped something new:
+
+**RelSpecGo**
+
+It started simple:
+
+* Initial LICENSE
+* Basic configuration
+* A direction
+
+By late December:
+
+* SQL writer implemented
+* Diff command added
+
+January 2026:
+
+* Documentation
+
+February 2026:
+
+* Schema editor UI (focused on relationships)
+* MSSQL DDL writer
+* Template support with `--from-list`
+
+---
+
+## April 2026: A Real Tool Emerges
+
+By April 2026, it became something I could finally stand behind.
+
+RelSpecGo reached version **1.0.44**, with:
+
+* Packaging for AUR, Debian, and RPM
+* Updated documentation and README
+* A full toolchain for:
+
+  * Convert
+  * Merge
+  * Inspect
+  * Diff
+  * Template
+  * Edit
+
+Support includes:
+
+* bun
+* dbml
+* drizzle
+* gorm
+* prisma
+* mssql
+* pgsql
+* sqlite
+
+Plus:
+
+* TUI editor
+* Template engine
+* Bidirectional schema handling
+
+👉 RelSpecGo: [https://git.warky.dev/wdevs/relspecgo](https://git.warky.dev/wdevs/relspecgo)
+
+This wasn’t just another generator anymore.
+It became a system for managing *database truth*.
+
+---
+
+## Lessons Learned (The Hard Way)
+
+This journey wasn’t about tools. It was about understanding databases properly.
+
+Here are the principles that stuck:
+
+### 1. Data Loss Is Not Acceptable
+
+Changing table structures should **never** result in lost data. If it does, the process is broken.
+
+### 2. Minimal Beats Clever
+
+The simpler the system, the easier it is to trust—and to fix.
+
+### 3. Respect the Database
+
+If you fight database rules, you will lose. Stay aligned with them.
+
+### 4. Indexes and Keys Matter More Than You Think
+
+Performance and correctness both depend on them. Ignore them at your own risk.
+
+### 5. Version-Control Your Backend Logic
+
+SQL scripts, functions, migrations—these must live in version control. No exceptions.
+
+### 6. It’s Not Migration—It’s Adaptation
+
+You’re not just moving data. You’re fixing inconsistencies and aligning systems.
+
+### 7. Migrations Never Go as Planned
+
+Always assume something will break. Plan for it.
+
+### 8. One Source of Truth Is Non-Negotiable
+
+Your database schema must have a single, authoritative definition.
+
+### 9. ORM Mapping Is a First-Class Concern
+
+Your application models must reflect the database correctly. Drift causes bugs.
+
+### 10. Audit Trails Are Critical
+
+If you can’t track changes, you can’t trust your system.
+
+### 11. Manage Database Functions Properly
+
+They are part of your system—not an afterthought.
+
+### 12. If It’s Hard to Understand, It’s Too Complex
+
+Clarity is a feature. Complexity is technical debt.
+
+### 13. GUIDs Have Their Place
+
+Especially when moving data across systems. They solve real problems.
+
+### 14. But Simplicity Still Wins
+
+Numbered primary keys are predictable, efficient, and easy to reason about.
+
+### 15. JSON Is Power—Use It Carefully
+
+It adds flexibility, but too much turns structure into chaos.
+
+---
+
+## Closing Thoughts
+
+Looking back, this wasn’t about building a tool.
+
+It was about:
+
+* Reducing friction
+* Making systems predictable
+* Respecting the database as the core of the system
+
+RelSpecGo is just the current result of that journey.
+
+Not the end.
+
+Just the first version that feels *right*.

pkg/pgsql/types_registry.go

@@ -0,0 +1,246 @@
+package pgsql
+
+import "strings"
+
+// TypeSpec describes PostgreSQL type capabilities used by parsers/writers.
+type TypeSpec struct {
+	SupportsLength    bool
+	SupportsPrecision bool
+}
+
+var postgresBaseTypes = map[string]TypeSpec{
+	// Numeric types
+	"smallint":         {},
+	"integer":          {},
+	"bigint":           {},
+	"decimal":          {SupportsPrecision: true},
+	"numeric":          {SupportsPrecision: true},
+	"real":             {},
+	"double precision": {},
+	"smallserial":      {},
+	"serial":           {},
+	"bigserial":        {},
+	"money":            {},
+
+	// Character types
+	"char":              {SupportsLength: true},
+	"character":         {SupportsLength: true},
+	"varchar":           {SupportsLength: true},
+	"character varying": {SupportsLength: true},
+	"text":              {},
+	"name":              {},
+
+	// Binary
+	"bytea": {},
+
+	// Date/time
+	"timestamp":                   {SupportsPrecision: true},
+	"timestamp without time zone": {SupportsPrecision: true},
+	"timestamp with time zone":    {SupportsPrecision: true},
+	"time":                        {SupportsPrecision: true},
+	"time without time zone":      {SupportsPrecision: true},
+	"time with time zone":         {SupportsPrecision: true},
+	"date":                        {},
+	"interval":                    {SupportsPrecision: true},
+
+	// Boolean
+	"boolean": {},
+
+	// Geometric
+	"point":   {},
+	"line":    {},
+	"lseg":    {},
+	"box":     {},
+	"path":    {},
+	"polygon": {},
+	"circle":  {},
+
+	// Network
+	"cidr":     {},
+	"inet":     {},
+	"macaddr":  {},
+	"macaddr8": {},
+
+	// Bit string
+	"bit":         {SupportsLength: true},
+	"bit varying": {SupportsLength: true},
+	"varbit":      {SupportsLength: true},
+
+	// Text search
+	"tsvector": {},
+	"tsquery":  {},
+
+	// UUID/XML/JSON
+	"uuid":  {},
+	"xml":   {},
+	"json":  {},
+	"jsonb": {},
+
+	// Range
+	"int4range":      {},
+	"int8range":      {},
+	"numrange":       {},
+	"tsrange":        {},
+	"tstzrange":      {},
+	"daterange":      {},
+	"int4multirange": {},
+	"int8multirange": {},
+	"nummultirange":  {},
+	"tsmultirange":   {},
+	"tstzmultirange": {},
+	"datemultirange": {},
+
+	// Object identifier
+	"oid":      {},
+	"regclass": {},
+	"regproc":  {},
+	"regtype":  {},
+
+	// Pseudo-ish/common built-ins seen in schemas
+	"record": {},
+	"void":   {},
+
+	// Common extensions
+	"citext":    {},
+	"hstore":    {},
+	"ltree":     {},
+	"lquery":    {},
+	"ltxtquery": {},
+	"vector":    {SupportsLength: true}, // pgvector: vector(dim)
+	"halfvec":   {SupportsLength: true}, // pgvector: halfvec(dim)
+	"sparsevec": {SupportsLength: true}, // pgvector: sparsevec(dim)
+}
+
+var postgresTypeAliases = map[string]string{
+	// Integer aliases
+	"int2": "smallint",
+	"int4": "integer",
+	"int8": "bigint",
+	"int":  "integer",
+
+	// Serial aliases
+	"serial2": "smallserial",
+	"serial4": "serial",
+	"serial8": "bigserial",
+
+	// Character aliases
+	"bpchar": "char",
+
+	// Float aliases
+	"float4": "real",
+	"float8": "double precision",
+	"float":  "double precision",
+
+	// Time aliases
+	"timestamptz": "timestamp with time zone",
+	"timetz":      "time with time zone",
+
+	// Bit alias
+	"varbit": "bit varying",
+
+	// Boolean alias
+	"bool": "boolean",
+}
+
+// GetPostgresBaseTypes returns a sorted-ish stable list of registered base type names.
+func GetPostgresBaseTypes() []string {
+	result := make([]string, 0, len(postgresBaseTypes))
+	for t := range postgresBaseTypes {
+		result = append(result, t)
+	}
+	return result
+}
+
+// GetPostgresTypes returns the registered PostgreSQL types.
+// When includeArrays is true, each base type also includes an array variant ("type[]").
+func GetPostgresTypes(includeArrays bool) []string {
+	base := GetPostgresBaseTypes()
+	if !includeArrays {
+		return base
+	}
+
+	result := make([]string, 0, len(base)*2)
+	result = append(result, base...)
+	for _, t := range base {
+		result = append(result, t+"[]")
+	}
+	return result
+}
+
+// ExtractBaseType returns the type without outer array suffixes and modifiers.
+// Examples:
+// - varchar(255) -> varchar
+// - text[] -> text
+// - numeric(10,2)[] -> numeric
+func ExtractBaseType(sqlType string) string {
+	t := normalizeTypeToken(sqlType)
+	t = strings.TrimSpace(stripArraySuffixes(t))
+	if idx := strings.Index(t, "("); idx > 0 {
+		t = strings.TrimSpace(t[:idx])
+	}
+	return t
+}
+
+// ExtractBaseTypeLower is ExtractBaseType with lowercase normalization.
+func ExtractBaseTypeLower(sqlType string) string {
+	return strings.ToLower(ExtractBaseType(sqlType))
+}
+
+// IsArrayType reports whether the SQL type has one or more [] suffixes.
+func IsArrayType(sqlType string) bool {
+	t := normalizeTypeToken(sqlType)
+	return strings.HasSuffix(t, "[]")
+}
+
+// ElementType returns the underlying element type for array types.
+// For non-array types, it returns the input unchanged.
+func ElementType(sqlType string) string {
+	t := normalizeTypeToken(sqlType)
+	return stripArraySuffixes(t)
+}
+
+// CanonicalizeBaseType resolves aliases to canonical PostgreSQL type names.
+func CanonicalizeBaseType(baseType string) string {
+	base := strings.ToLower(normalizeTypeToken(baseType))
+	if canonical, ok := postgresTypeAliases[base]; ok {
+		return canonical
+	}
+	return base
+}
+
+// IsKnownPostgresType reports whether a type (including array forms) exists in the registry.
+func IsKnownPostgresType(sqlType string) bool {
+	base := CanonicalizeBaseType(ExtractBaseTypeLower(sqlType))
+	_, ok := postgresBaseTypes[base]
+	return ok
+}
+
+// SupportsLength reports if this SQL type accepts a single length/dimension modifier.
+func SupportsLength(sqlType string) bool {
+	base := CanonicalizeBaseType(ExtractBaseTypeLower(sqlType))
+	spec, ok := postgresBaseTypes[base]
+	return ok && spec.SupportsLength
+}
+
+// SupportsPrecision reports if this SQL type accepts precision (and possibly scale).
+func SupportsPrecision(sqlType string) bool {
+	base := CanonicalizeBaseType(ExtractBaseTypeLower(sqlType))
+	spec, ok := postgresBaseTypes[base]
+	return ok && spec.SupportsPrecision
+}
+
+// HasExplicitTypeModifier reports if the type already includes "(...)".
+func HasExplicitTypeModifier(sqlType string) bool {
+	return strings.Contains(sqlType, "(")
+}
+
+func stripArraySuffixes(t string) string {
+	for strings.HasSuffix(t, "[]") {
+		t = strings.TrimSpace(strings.TrimSuffix(t, "[]"))
+	}
+	return t
+}
+
+func normalizeTypeToken(t string) string {
+	return strings.Join(strings.Fields(strings.TrimSpace(t)), " ")
+}

pkg/pgsql/types_registry_test.go

@@ -0,0 +1,99 @@
+package pgsql
+
+import "testing"
+
+func TestPostgresTypeRegistry_MasterListIncludesRequestedTypes(t *testing.T) {
+	required := []string{
+		"vector",
+		"integer",
+		"citext",
+	}
+
+	types := make(map[string]bool)
+	for _, typ := range GetPostgresTypes(true) {
+		types[typ] = true
+	}
+
+	for _, typ := range required {
+		if !types[typ] {
+			t.Fatalf("master type list missing %q", typ)
+		}
+		if !types[typ+"[]"] {
+			t.Fatalf("master type list missing array variant %q", typ+"[]")
+		}
+	}
+}
+
+func TestPostgresTypeRegistry_TypeParsingAndCapabilities(t *testing.T) {
+	tests := []struct {
+		input             string
+		wantBase          string
+		wantCanonicalBase string
+		wantArray         bool
+		wantKnown         bool
+		wantLength        bool
+		wantPrecision     bool
+	}{
+		{
+			input:             "integer[]",
+			wantBase:          "integer",
+			wantCanonicalBase: "integer",
+			wantArray:         true,
+			wantKnown:         true,
+		},
+		{
+			input:             "citext[]",
+			wantBase:          "citext",
+			wantCanonicalBase: "citext",
+			wantArray:         true,
+			wantKnown:         true,
+		},
+		{
+			input:             "vector(1536)",
+			wantBase:          "vector",
+			wantCanonicalBase: "vector",
+			wantKnown:         true,
+			wantLength:        true,
+		},
+		{
+			input:             "numeric(10,2)",
+			wantBase:          "numeric",
+			wantCanonicalBase: "numeric",
+			wantKnown:         true,
+			wantPrecision:     true,
+		},
+		{
+			input:             "int4",
+			wantBase:          "int4",
+			wantCanonicalBase: "integer",
+			wantKnown:         true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			base := ExtractBaseTypeLower(tt.input)
+			if base != tt.wantBase {
+				t.Fatalf("ExtractBaseTypeLower(%q) = %q, want %q", tt.input, base, tt.wantBase)
+			}
+
+			canonical := CanonicalizeBaseType(base)
+			if canonical != tt.wantCanonicalBase {
+				t.Fatalf("CanonicalizeBaseType(%q) = %q, want %q", base, canonical, tt.wantCanonicalBase)
+			}
+
+			if IsArrayType(tt.input) != tt.wantArray {
+				t.Fatalf("IsArrayType(%q) = %v, want %v", tt.input, IsArrayType(tt.input), tt.wantArray)
+			}
+			if IsKnownPostgresType(tt.input) != tt.wantKnown {
+				t.Fatalf("IsKnownPostgresType(%q) = %v, want %v", tt.input, IsKnownPostgresType(tt.input), tt.wantKnown)
+			}
+			if SupportsLength(tt.input) != tt.wantLength {
+				t.Fatalf("SupportsLength(%q) = %v, want %v", tt.input, SupportsLength(tt.input), tt.wantLength)
+			}
+			if SupportsPrecision(tt.input) != tt.wantPrecision {
+				t.Fatalf("SupportsPrecision(%q) = %v, want %v", tt.input, SupportsPrecision(tt.input), tt.wantPrecision)
+			}
+		})
+	}
+}

pkg/readers/bun/reader.go

@@ -12,6 +12,7 @@ import (
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 	"git.warky.dev/wdevs/relspecgo/pkg/readers"
 )
 
@@ -700,16 +701,21 @@ func (r *Reader) extractBunTag(tag string) string {
 // parseTypeWithLength parses a type string and extracts length if present
 // e.g., "varchar(255)" returns ("varchar", 255)
 func (r *Reader) parseTypeWithLength(typeStr string) (baseType string, length int) {
+	typeStr = strings.TrimSpace(typeStr)
+	baseType = typeStr
+
 	// Check for type with length: varchar(255), char(10), etc.
 	re := regexp.MustCompile(`^([a-zA-Z\s]+)\((\d+)\)$`)
 	matches := re.FindStringSubmatch(typeStr)
 	if len(matches) == 3 {
+		rawBaseType := strings.TrimSpace(matches[1])
+		if pgsql.SupportsLength(rawBaseType) {
 			if _, err := fmt.Sscanf(matches[2], "%d", &length); err == nil {
-			baseType = strings.TrimSpace(matches[1])
 				return
 			}
 		}
-	baseType = typeStr
+	}
+
 	return
 }
 

pkg/readers/bun/reader_test.go

@@ -71,8 +71,11 @@ func TestReader_ReadDatabase_Simple(t *testing.T) {
 	if !emailCol.NotNull {
 		t.Error("Column 'email' should be NOT NULL (explicit 'notnull' tag)")
 	}
-	if emailCol.Type != "varchar" || emailCol.Length != 255 {
+	if emailCol.Type != "varchar" && emailCol.Type != "varchar(255)" {
-		t.Errorf("Expected email type 'varchar(255)', got '%s' with length %d", emailCol.Type, emailCol.Length)
+		t.Errorf("Expected email type 'varchar' or 'varchar(255)', got '%s' with length %d", emailCol.Type, emailCol.Length)
+	}
+	if emailCol.Length != 255 {
+		t.Errorf("Expected email length 255, got %d", emailCol.Length)
 	}
 
 	// Verify name column - primitive string type should be NOT NULL by default in Bun
@@ -356,6 +359,33 @@ func TestReader_ReadDatabase_Complex(t *testing.T) {
 	}
 }
 
+func TestParseTypeWithLength_PreservesExplicitTypeModifiers(t *testing.T) {
+	reader := &Reader{}
+
+	tests := []struct {
+		input      string
+		wantType   string
+		wantLength int
+	}{
+		{"varchar(255)", "varchar(255)", 255},
+		{"character varying(120)", "character varying(120)", 120},
+		{"vector(1536)", "vector(1536)", 1536},
+		{"numeric(10,2)", "numeric(10,2)", 0},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			gotType, gotLength := reader.parseTypeWithLength(tt.input)
+			if gotType != tt.wantType {
+				t.Fatalf("parseTypeWithLength(%q) type = %q, want %q", tt.input, gotType, tt.wantType)
+			}
+			if gotLength != tt.wantLength {
+				t.Fatalf("parseTypeWithLength(%q) length = %d, want %d", tt.input, gotLength, tt.wantLength)
+			}
+		})
+	}
+}
+
 func TestReader_ReadSchema(t *testing.T) {
 	opts := &readers.ReaderOptions{
 		FilePath: filepath.Join("..", "..", "..", "tests", "assets", "bun", "simple.go"),

pkg/readers/dbml/reader.go

@@ -567,25 +567,20 @@ func (r *Reader) parseDBML(content string) (*models.Database, error) {
 // parseColumn parses a DBML column definition
 func (r *Reader) parseColumn(line, tableName, schemaName string) (*models.Column, *models.Constraint) {
 	// Format: column_name type [attributes] // comment
-	parts := strings.Fields(line)
+	lineNoComment, inlineComment := splitInlineComment(line)
-	if len(parts) < 2 {
+	signature, attrs := splitColumnSignatureAndAttrs(lineNoComment)
+	columnName, columnType, ok := parseColumnSignature(signature)
+	if !ok {
 		return nil, nil
 	}
 
-	columnName := stripQuotes(parts[0])
-	columnType := stripQuotes(parts[1])
-
 	column := models.InitColumn(columnName, tableName, schemaName)
 	column.Type = columnType
 
 	var constraint *models.Constraint
 
 	// Parse attributes in brackets
-	if strings.Contains(line, "[") && strings.Contains(line, "]") {
+	if attrs != "" {
-		attrStart := strings.Index(line, "[")
-		attrEnd := strings.Index(line, "]")
-		if attrStart < attrEnd {
-			attrs := line[attrStart+1 : attrEnd]
 		attrList := strings.Split(attrs, ",")
 
 		for _, attr := range attrList {
@@ -660,17 +655,94 @@ func (r *Reader) parseColumn(line, tableName, schemaName string) (*models.Column
 			}
 		}
 	}
-	}
 
 	// Parse inline comment
-	if strings.Contains(line, "//") {
+	if inlineComment != "" {
-		commentStart := strings.Index(line, "//")
+		column.Comment = inlineComment
-		column.Comment = strings.TrimSpace(line[commentStart+2:])
 	}
 
 	return column, constraint
 }
 
+func splitInlineComment(line string) (string, string) {
+	commentStart := strings.Index(line, "//")
+	if commentStart == -1 {
+		return line, ""
+	}
+
+	return strings.TrimSpace(line[:commentStart]), strings.TrimSpace(line[commentStart+2:])
+}
+
+func splitColumnSignatureAndAttrs(line string) (string, string) {
+	trimmed := strings.TrimSpace(line)
+	if trimmed == "" || !strings.HasSuffix(trimmed, "]") {
+		return trimmed, ""
+	}
+
+	bracketDepth := 0
+	for i := len(trimmed) - 1; i >= 0; i-- {
+		switch trimmed[i] {
+		case ']':
+			bracketDepth++
+		case '[':
+			bracketDepth--
+			if bracketDepth == 0 {
+				// DBML attributes are a trailing [ ... ] block preceded by whitespace.
+				// This avoids confusing array types like text[] with attribute blocks.
+				if i > 0 && (trimmed[i-1] == ' ' || trimmed[i-1] == '\t') {
+					return strings.TrimSpace(trimmed[:i]), strings.TrimSpace(trimmed[i+1 : len(trimmed)-1])
+				}
+			}
+		}
+	}
+
+	return trimmed, ""
+}
+
+func parseColumnSignature(signature string) (string, string, bool) {
+	signature = strings.TrimSpace(signature)
+	if signature == "" {
+		return "", "", false
+	}
+
+	var splitAt int
+	if signature[0] == '"' || signature[0] == '\'' {
+		quote := signature[0]
+		splitAt = 1
+		for splitAt < len(signature) {
+			if signature[splitAt] == quote {
+				splitAt++
+				break
+			}
+			splitAt++
+		}
+	} else {
+		for splitAt < len(signature) && signature[splitAt] != ' ' && signature[splitAt] != '\t' {
+			splitAt++
+		}
+	}
+
+	if splitAt <= 0 || splitAt >= len(signature) {
+		return "", "", false
+	}
+
+	columnName := stripQuotes(strings.TrimSpace(signature[:splitAt]))
+	columnType := stripWrappingQuotes(strings.TrimSpace(signature[splitAt:]))
+	if columnName == "" || columnType == "" {
+		return "", "", false
+	}
+
+	return columnName, columnType, true
+}
+
+func stripWrappingQuotes(s string) string {
+	s = strings.TrimSpace(s)
+	if len(s) >= 2 && ((s[0] == '"' && s[len(s)-1] == '"') || (s[0] == '\'' && s[len(s)-1] == '\'')) {
+		return s[1 : len(s)-1]
+	}
+	return s
+}
+
 // parseIndex parses a DBML index definition
 func (r *Reader) parseIndex(line, tableName, schemaName string) *models.Index {
 	// Format: (columns) [attributes] OR columnname [attributes]

pkg/readers/dbml/reader_test.go

@@ -839,6 +839,67 @@ func TestConstraintNaming(t *testing.T) {
 	}
 }
 
+func TestParseColumn_PostgresTypes(t *testing.T) {
+	reader := &Reader{}
+
+	tests := []struct {
+		name        string
+		line        string
+		wantName    string
+		wantType    string
+		wantNotNull bool
+		wantComment string
+	}{
+		{
+			name:        "array type with attrs",
+			line:        "tags text[] [not null]",
+			wantName:    "tags",
+			wantType:    "text[]",
+			wantNotNull: true,
+		},
+		{
+			name:     "vector with dimension",
+			line:     "embedding vector(1536)",
+			wantName: "embedding",
+			wantType: "vector(1536)",
+		},
+		{
+			name:     "multi word timestamp type",
+			line:     "published_at timestamp with time zone",
+			wantName: "published_at",
+			wantType: "timestamp with time zone",
+		},
+		{
+			name:        "array type with inline comment",
+			line:        "labels varchar(20)[] // column labels",
+			wantName:    "labels",
+			wantType:    "varchar(20)[]",
+			wantComment: "column labels",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			col, _ := reader.parseColumn(tt.line, "events", "public")
+			if col == nil {
+				t.Fatalf("parseColumn() returned nil column")
+			}
+			if col.Name != tt.wantName {
+				t.Errorf("column name = %q, want %q", col.Name, tt.wantName)
+			}
+			if col.Type != tt.wantType {
+				t.Errorf("column type = %q, want %q", col.Type, tt.wantType)
+			}
+			if col.NotNull != tt.wantNotNull {
+				t.Errorf("column not null = %v, want %v", col.NotNull, tt.wantNotNull)
+			}
+			if col.Comment != tt.wantComment {
+				t.Errorf("column comment = %q, want %q", col.Comment, tt.wantComment)
+			}
+		})
+	}
+}
+
 func getKeys[V any](m map[string]V) []string {
 	keys := make([]string, 0, len(m))
 	for k := range m {

pkg/readers/dctx/reader.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 	"git.warky.dev/wdevs/relspecgo/pkg/readers"
 )
 
@@ -232,7 +233,19 @@ func (r *Reader) convertField(dctxField *models.DCTXField, tableName string) ([]
 
 // mapDataType maps Clarion data types to SQL types
 func (r *Reader) mapDataType(clarionType string, size int) (sqlType string, precision int) {
-	switch strings.ToUpper(clarionType) {
+	trimmedType := strings.TrimSpace(clarionType)
+
+	// Preserve known PostgreSQL types (including arrays and extension types)
+	// from DCTX input instead of coercing them to generic text.
+	if pgsql.IsKnownPostgresType(trimmedType) {
+		pgType := canonicalizePostgresType(trimmedType)
+		if !pgsql.HasExplicitTypeModifier(pgType) && size > 0 && pgsql.SupportsLength(pgType) {
+			return pgType, size
+		}
+		return pgType, 0
+	}
+
+	switch strings.ToUpper(trimmedType) {
 	case "LONG":
 		if size == 8 {
 			return "bigint", 0
@@ -306,6 +319,32 @@ func (r *Reader) mapDataType(clarionType string, size int) (sqlType string, prec
 	}
 }
 
+func canonicalizePostgresType(typeStr string) string {
+	t := strings.ToLower(strings.Join(strings.Fields(strings.TrimSpace(typeStr)), " "))
+	if t == "" {
+		return ""
+	}
+
+	// Handle array suffixes
+	arrayCount := 0
+	for strings.HasSuffix(t, "[]") {
+		arrayCount++
+		t = strings.TrimSpace(strings.TrimSuffix(t, "[]"))
+	}
+
+	// Handle optional type modifier
+	modifier := ""
+	if idx := strings.Index(t, "("); idx > 0 {
+		if end := strings.LastIndex(t, ")"); end > idx {
+			modifier = t[idx : end+1]
+			t = strings.TrimSpace(t[:idx])
+		}
+	}
+
+	base := pgsql.CanonicalizeBaseType(t)
+	return base + modifier + strings.Repeat("[]", arrayCount)
+}
+
 // processKeys processes DCTX keys and converts them to indexes and primary keys
 func (r *Reader) processKeys(dctxTable *models.DCTXTable, table *models.Table, fieldGuidMap map[string]string) error {
 	for _, dctxKey := range dctxTable.Keys {

pkg/readers/dctx/reader_test.go

@@ -493,3 +493,55 @@ func TestRelationships(t *testing.T) {
 		}
 	}
 }
+
+func TestMapDataType_PostgresTypes(t *testing.T) {
+	reader := &Reader{}
+
+	tests := []struct {
+		name       string
+		inputType  string
+		size       int
+		wantType   string
+		wantLength int
+	}{
+		{
+			name:      "integer array preserved",
+			inputType: "integer[]",
+			wantType:  "integer[]",
+		},
+		{
+			name:      "citext array preserved",
+			inputType: "citext[]",
+			wantType:  "citext[]",
+		},
+		{
+			name:      "vector modifier preserved",
+			inputType: "vector(1536)",
+			wantType:  "vector(1536)",
+		},
+		{
+			name:      "alias canonicalized in array",
+			inputType: "int4[]",
+			wantType:  "integer[]",
+		},
+		{
+			name:       "varchar length from size",
+			inputType:  "varchar",
+			size:       120,
+			wantType:   "varchar",
+			wantLength: 120,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotType, gotLength := reader.mapDataType(tt.inputType, tt.size)
+			if gotType != tt.wantType {
+				t.Fatalf("mapDataType(%q, %d) type = %q, want %q", tt.inputType, tt.size, gotType, tt.wantType)
+			}
+			if gotLength != tt.wantLength {
+				t.Fatalf("mapDataType(%q, %d) length = %d, want %d", tt.inputType, tt.size, gotLength, tt.wantLength)
+			}
+		})
+	}
+}

pkg/readers/drawdb/reader.go

@@ -8,6 +8,7 @@ import (
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 	"git.warky.dev/wdevs/relspecgo/pkg/readers"
 	"git.warky.dev/wdevs/relspecgo/pkg/writers/drawdb"
 )
@@ -231,17 +232,19 @@ func (r *Reader) convertToColumn(field *drawdb.DrawDBField, tableName, schemaNam
 
 	// Parse type and dimensions
 	typeStr := field.Type
+	typeStr = strings.TrimSpace(typeStr)
 	column.Type = typeStr
 
 	// Try to extract length/precision from type string like "varchar(255)" or "decimal(10,2)"
 	if strings.Contains(typeStr, "(") {
 		parts := strings.Split(typeStr, "(")
-		column.Type = parts[0]
+		baseType := strings.TrimSpace(parts[0])
 
 		if len(parts) > 1 {
 			dimensions := strings.TrimSuffix(parts[1], ")")
 			if strings.Contains(dimensions, ",") {
-				// Precision and scale (e.g., decimal(10,2))
+				// Precision and scale (e.g., decimal(10,2), numeric(10,2))
+				if pgsql.SupportsPrecision(baseType) {
 					dims := strings.Split(dimensions, ",")
 					if precision, err := strconv.Atoi(strings.TrimSpace(dims[0])); err == nil {
 						column.Precision = precision
@@ -251,14 +254,17 @@ func (r *Reader) convertToColumn(field *drawdb.DrawDBField, tableName, schemaNam
 							column.Scale = scale
 						}
 					}
+				}
 			} else {
 				// Just length (e.g., varchar(255))
+				if pgsql.SupportsLength(baseType) {
 					if length, err := strconv.Atoi(dimensions); err == nil {
 						column.Length = length
 					}
 				}
 			}
 		}
+	}
 
 	column.IsPrimaryKey = field.Primary
 	column.NotNull = field.NotNull || field.Primary

pkg/readers/drawdb/reader_test.go

@@ -6,6 +6,7 @@ import (
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
 	"git.warky.dev/wdevs/relspecgo/pkg/readers"
+	"git.warky.dev/wdevs/relspecgo/pkg/writers/drawdb"
 )
 
 func TestReader_ReadDatabase_Simple(t *testing.T) {
@@ -288,6 +289,61 @@ func TestReader_ReadDatabase_Complex(t *testing.T) {
 	}
 }
 
+func TestConvertToColumn_PreservesExplicitTypeModifiers(t *testing.T) {
+	reader := &Reader{}
+
+	tests := []struct {
+		name          string
+		fieldType     string
+		wantType      string
+		wantLength    int
+		wantPrecision int
+		wantScale     int
+	}{
+		{
+			name:       "varchar with length",
+			fieldType:  "varchar(255)",
+			wantType:   "varchar(255)",
+			wantLength: 255,
+		},
+		{
+			name:          "numeric precision/scale",
+			fieldType:     "numeric(10,2)",
+			wantType:      "numeric(10,2)",
+			wantPrecision: 10,
+			wantScale:     2,
+		},
+		{
+			name:       "custom vector modifier",
+			fieldType:  "vector(1536)",
+			wantType:   "vector(1536)",
+			wantLength: 1536,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			field := &drawdb.DrawDBField{
+				Name: tt.name,
+				Type: tt.fieldType,
+			}
+			col := reader.convertToColumn(field, "events", "public")
+			if col.Type != tt.wantType {
+				t.Fatalf("column type = %q, want %q", col.Type, tt.wantType)
+			}
+			if col.Length != tt.wantLength {
+				t.Fatalf("column length = %d, want %d", col.Length, tt.wantLength)
+			}
+			if col.Precision != tt.wantPrecision {
+				t.Fatalf("column precision = %d, want %d", col.Precision, tt.wantPrecision)
+			}
+			if col.Scale != tt.wantScale {
+				t.Fatalf("column scale = %d, want %d", col.Scale, tt.wantScale)
+			}
+		})
+	}
+}
+
 func TestReader_ReadSchema(t *testing.T) {
 	opts := &readers.ReaderOptions{
 		FilePath: filepath.Join("..", "..", "..", "tests", "assets", "drawdb", "simple.json"),

pkg/readers/gorm/reader.go

@@ -12,6 +12,7 @@ import (
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 	"git.warky.dev/wdevs/relspecgo/pkg/readers"
 )
 
@@ -784,11 +785,14 @@ func (r *Reader) extractGormTag(tag string) string {
 // parseTypeWithLength parses a type string and extracts length if present
 // e.g., "varchar(255)" returns ("varchar", 255)
 func (r *Reader) parseTypeWithLength(typeStr string) (baseType string, length int) {
+	typeStr = strings.TrimSpace(typeStr)
+	baseType = typeStr
+
 	// Check for type with length: varchar(255), char(10), etc.
 	// Also handle precision/scale: numeric(10,2)
 	if strings.Contains(typeStr, "(") {
 		idx := strings.Index(typeStr, "(")
-		baseType = strings.TrimSpace(typeStr[:idx])
+		rawBaseType := strings.TrimSpace(typeStr[:idx])
 
 		// Extract numbers from parentheses
 		parens := typeStr[idx+1:]
@@ -796,14 +800,15 @@ func (r *Reader) parseTypeWithLength(typeStr string) (baseType string, length in
 			parens = parens[:endIdx]
 		}
 
-		// For now, just handle single number (length)
+		// Only treat as "length" for text-ish SQL types.
-		if !strings.Contains(parens, ",") {
+		// This avoids converting custom modifiers like vector(1536) into Length.
+		if pgsql.SupportsLength(rawBaseType) && !strings.Contains(parens, ",") {
 			if _, err := fmt.Sscanf(parens, "%d", &length); err == nil {
 				return
 			}
 		}
 	}
-	baseType = typeStr
+
 	return
 }
 

pkg/readers/gorm/reader_test.go

@@ -71,8 +71,11 @@ func TestReader_ReadDatabase_Simple(t *testing.T) {
 	if !emailCol.NotNull {
 		t.Error("Column 'email' should be NOT NULL (explicit 'not null' tag)")
 	}
-	if emailCol.Type != "varchar" || emailCol.Length != 255 {
+	if emailCol.Type != "varchar" && emailCol.Type != "varchar(255)" {
-		t.Errorf("Expected email type 'varchar(255)', got '%s' with length %d", emailCol.Type, emailCol.Length)
+		t.Errorf("Expected email type 'varchar' or 'varchar(255)', got '%s' with length %d", emailCol.Type, emailCol.Length)
+	}
+	if emailCol.Length != 255 {
+		t.Errorf("Expected email length 255, got %d", emailCol.Length)
 	}
 
 	// Verify name column - primitive string type should be NOT NULL by default
@@ -363,6 +366,33 @@ func TestReader_ReadDatabase_Complex(t *testing.T) {
 	}
 }
 
+func TestParseTypeWithLength_PreservesExplicitTypeModifiers(t *testing.T) {
+	reader := &Reader{}
+
+	tests := []struct {
+		input      string
+		wantType   string
+		wantLength int
+	}{
+		{"varchar(255)", "varchar(255)", 255},
+		{"character varying(120)", "character varying(120)", 120},
+		{"vector(1536)", "vector(1536)", 1536},
+		{"numeric(10,2)", "numeric(10,2)", 0},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			gotType, gotLength := reader.parseTypeWithLength(tt.input)
+			if gotType != tt.wantType {
+				t.Fatalf("parseTypeWithLength(%q) type = %q, want %q", tt.input, gotType, tt.wantType)
+			}
+			if gotLength != tt.wantLength {
+				t.Fatalf("parseTypeWithLength(%q) length = %d, want %d", tt.input, gotLength, tt.wantLength)
+			}
+		})
+	}
+}
+
 func TestReader_ReadSchema(t *testing.T) {
 	opts := &readers.ReaderOptions{
 		FilePath: filepath.Join("..", "..", "..", "tests", "assets", "gorm", "simple.go"),

pkg/readers/pgsql/queries.go

@@ -206,8 +206,19 @@ func (r *Reader) queryColumns(schemaName string) (map[string]map[string]*models.
 			c.numeric_precision,
 			c.numeric_scale,
 			c.udt_name,
+			pg_catalog.format_type(a.atttypid, a.atttypmod) as formatted_data_type,
 			col_description((c.table_schema||'.'||c.table_name)::regclass, c.ordinal_position) as description
 		FROM information_schema.columns c
+		JOIN pg_catalog.pg_namespace n
+			ON n.nspname = c.table_schema
+		JOIN pg_catalog.pg_class cls
+			ON cls.relname = c.table_name
+			AND cls.relnamespace = n.oid
+		JOIN pg_catalog.pg_attribute a
+			ON a.attrelid = cls.oid
+			AND a.attname = c.column_name
+			AND a.attnum > 0
+			AND NOT a.attisdropped
 		WHERE c.table_schema = $1
 		ORDER BY c.table_schema, c.table_name, c.ordinal_position
 	`
@@ -221,12 +232,12 @@ func (r *Reader) queryColumns(schemaName string) (map[string]map[string]*models.
 	columnsMap := make(map[string]map[string]*models.Column)
 
 	for rows.Next() {
-		var schema, tableName, columnName, isNullable, dataType, udtName string
+		var schema, tableName, columnName, isNullable, dataType, udtName, formattedDataType string
 		var ordinalPosition int
 		var columnDefault, description *string
 		var charMaxLength, numPrecision, numScale *int
 
-		if err := rows.Scan(&schema, &tableName, &columnName, &ordinalPosition, &columnDefault, &isNullable, &dataType, &charMaxLength, &numPrecision, &numScale, &udtName, &description); err != nil {
+		if err := rows.Scan(&schema, &tableName, &columnName, &ordinalPosition, &columnDefault, &isNullable, &dataType, &charMaxLength, &numPrecision, &numScale, &udtName, &formattedDataType, &description); err != nil {
 			return nil, err
 		}
 
@@ -246,7 +257,7 @@ func (r *Reader) queryColumns(schemaName string) (map[string]map[string]*models.
 		}
 
 		// Map data type, preserving serial types when detected
-		column.Type = r.mapDataType(dataType, udtName, hasNextval)
+		column.Type = r.mapDataType(dataType, udtName, formattedDataType, hasNextval)
 		column.NotNull = (isNullable == "NO")
 		column.Sequence = uint(ordinalPosition)
 

pkg/readers/pgsql/reader.go

@@ -259,12 +259,14 @@ func (r *Reader) close() {
 	}
 }
 
-// mapDataType maps PostgreSQL data types to canonical types
+// mapDataType maps PostgreSQL data types while preserving exact type text when available.
-func (r *Reader) mapDataType(pgType, udtName string, hasNextval bool) string {
+func (r *Reader) mapDataType(pgType, udtName, formattedType string, hasNextval bool) string {
+	normalizedPGType := strings.ToLower(strings.TrimSpace(pgType))
+
 	// If the column has a nextval default, it's likely a serial type
 	// Map to the appropriate serial type instead of the base integer type
 	if hasNextval {
-		switch strings.ToLower(pgType) {
+		switch normalizedPGType {
 		case "integer", "int", "int4":
 			return "serial"
 		case "bigint", "int8":
@@ -274,6 +276,17 @@ func (r *Reader) mapDataType(pgType, udtName string, hasNextval bool) string {
 		}
 	}
 
+	// Prefer the database-provided formatted type; this preserves arrays/custom
+	// types/modifiers like text[], vector(1536), numeric(10,2), etc.
+	if strings.TrimSpace(formattedType) != "" {
+		return formattedType
+	}
+
+	// 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:] + "[]"
+	}
+
 	// Map common PostgreSQL types
 	typeMap := map[string]string{
 		"integer":                     "integer",
@@ -320,7 +333,7 @@ func (r *Reader) mapDataType(pgType, udtName string, hasNextval bool) string {
 	}
 
 	// Try mapped type first
-	if mapped, exists := typeMap[pgType]; exists {
+	if mapped, exists := typeMap[normalizedPGType]; exists {
 		return mapped
 	}
 
@@ -329,8 +342,11 @@ func (r *Reader) mapDataType(pgType, udtName string, hasNextval bool) string {
 		return pgsql.GetSQLType(pgType)
 	}
 
-	// Return UDT name for custom types
+	// Return UDT name for custom types (including array fallback when needed)
 	if udtName != "" {
+		if strings.HasPrefix(udtName, "_") && len(udtName) > 1 {
+			return udtName[1:] + "[]"
+		}
 		return udtName
 	}
 

pkg/readers/pgsql/reader_test.go

@@ -175,33 +175,37 @@ func TestMapDataType(t *testing.T) {
 	tests := []struct {
 		pgType        string
 		udtName       string
+		formattedType string
 		expected      string
 	}{
-		{"integer", "int4", "integer"},
+		{"integer", "int4", "", "integer"},
-		{"bigint", "int8", "bigint"},
+		{"bigint", "int8", "", "bigint"},
-		{"smallint", "int2", "smallint"},
+		{"smallint", "int2", "", "smallint"},
-		{"character varying", "varchar", "varchar"},
+		{"character varying", "varchar", "", "varchar"},
-		{"text", "text", "text"},
+		{"text", "text", "", "text"},
-		{"boolean", "bool", "boolean"},
+		{"boolean", "bool", "", "boolean"},
-		{"timestamp without time zone", "timestamp", "timestamp"},
+		{"timestamp without time zone", "timestamp", "", "timestamp"},
-		{"timestamp with time zone", "timestamptz", "timestamptz"},
+		{"timestamp with time zone", "timestamptz", "", "timestamptz"},
-		{"json", "json", "json"},
+		{"json", "json", "", "json"},
-		{"jsonb", "jsonb", "jsonb"},
+		{"jsonb", "jsonb", "", "jsonb"},
-		{"uuid", "uuid", "uuid"},
+		{"uuid", "uuid", "", "uuid"},
-		{"numeric", "numeric", "numeric"},
+		{"numeric", "numeric", "", "numeric"},
-		{"real", "float4", "real"},
+		{"real", "float4", "", "real"},
-		{"double precision", "float8", "double precision"},
+		{"double precision", "float8", "", "double precision"},
-		{"date", "date", "date"},
+		{"date", "date", "", "date"},
-		{"time without time zone", "time", "time"},
+		{"time without time zone", "time", "", "time"},
-		{"bytea", "bytea", "bytea"},
+		{"bytea", "bytea", "", "bytea"},
-		{"unknown_type", "custom", "custom"}, // Should return UDT name
+		{"unknown_type", "custom", "", "custom"}, // Should return UDT name
+		{"ARRAY", "_text", "", "text[]"},
+		{"USER-DEFINED", "vector", "vector(1536)", "vector(1536)"},
+		{"character varying", "varchar", "character varying(255)", "character varying(255)"},
 	}
 
 	for _, tt := range tests {
 		t.Run(tt.pgType, func(t *testing.T) {
-			result := reader.mapDataType(tt.pgType, tt.udtName, false)
+			result := reader.mapDataType(tt.pgType, tt.udtName, tt.formattedType, false)
 			if result != tt.expected {
-				t.Errorf("mapDataType(%s, %s) = %s, expected %s", tt.pgType, tt.udtName, result, tt.expected)
+				t.Errorf("mapDataType(%s, %s, %s) = %s, expected %s", tt.pgType, tt.udtName, tt.formattedType, result, tt.expected)
 			}
 		})
 	}
@@ -218,9 +222,9 @@ func TestMapDataType(t *testing.T) {
 
 	for _, tt := range serialTests {
 		t.Run(tt.pgType+"_with_nextval", func(t *testing.T) {
-			result := reader.mapDataType(tt.pgType, "", true)
+			result := reader.mapDataType(tt.pgType, "", "", true)
 			if result != tt.expected {
-				t.Errorf("mapDataType(%s, '', true) = %s, expected %s", tt.pgType, result, tt.expected)
+				t.Errorf("mapDataType(%s, '', '', true) = %s, expected %s", tt.pgType, result, tt.expected)
 			}
 		})
 	}

pkg/readers/typeorm/reader.go

@@ -5,9 +5,11 @@ import (
 	"fmt"
 	"os"
 	"regexp"
+	"strconv"
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 	"git.warky.dev/wdevs/relspecgo/pkg/readers"
 )
 
@@ -549,6 +551,41 @@ func (r *Reader) parseColumnOptions(decorator string, column *models.Column, tab
 		}
 	}
 
+	// Preserve explicit type modifiers from options where present.
+	// Example: @Column({ type: 'varchar', length: 255 }) -> varchar(255)
+	if column.Type != "" && !strings.Contains(column.Type, "(") {
+		lengthRegex := regexp.MustCompile(`length:\s*(\d+)`)
+		precisionRegex := regexp.MustCompile(`precision:\s*(\d+)`)
+		scaleRegex := regexp.MustCompile(`scale:\s*(\d+)`)
+
+		baseType := strings.ToLower(strings.TrimSpace(column.Type))
+
+		if pgsql.SupportsLength(baseType) {
+			if matches := lengthRegex.FindStringSubmatch(content); len(matches) == 2 {
+				if n, err := strconv.Atoi(matches[1]); err == nil && n > 0 {
+					column.Length = n
+					column.Type = fmt.Sprintf("%s(%d)", column.Type, n)
+				}
+			}
+		}
+
+		if pgsql.SupportsPrecision(baseType) {
+			if matches := precisionRegex.FindStringSubmatch(content); len(matches) == 2 {
+				if p, err := strconv.Atoi(matches[1]); err == nil && p > 0 {
+					column.Precision = p
+					if sm := scaleRegex.FindStringSubmatch(content); len(sm) == 2 {
+						if s, err := strconv.Atoi(sm[1]); err == nil && s >= 0 {
+							column.Scale = s
+							column.Type = fmt.Sprintf("%s(%d,%d)", column.Type, p, s)
+						}
+					} else {
+						column.Type = fmt.Sprintf("%s(%d)", column.Type, p)
+					}
+				}
+			}
+		}
+	}
+
 	if strings.Contains(content, "nullable: true") || strings.Contains(content, "nullable:true") {
 		column.NotNull = false
 	}

pkg/readers/typeorm/reader_test.go

@@ -0,0 +1,60 @@
+package typeorm
+
+import (
+	"testing"
+
+	"git.warky.dev/wdevs/relspecgo/pkg/models"
+)
+
+func TestParseColumnOptions_PreservesTypeModifiers(t *testing.T) {
+	reader := &Reader{}
+	table := models.InitTable("users", "public")
+
+	tests := []struct {
+		name          string
+		decorator     string
+		wantType      string
+		wantLength    int
+		wantPrecision int
+		wantScale     int
+	}{
+		{
+			name:       "varchar with length",
+			decorator:  `@Column({ type: 'varchar', length: 255 })`,
+			wantType:   "varchar(255)",
+			wantLength: 255,
+		},
+		{
+			name:          "numeric with precision and scale",
+			decorator:     `@Column({ type: 'numeric', precision: 10, scale: 2 })`,
+			wantType:      "numeric(10,2)",
+			wantPrecision: 10,
+			wantScale:     2,
+		},
+		{
+			name:      "custom type with explicit modifier is preserved",
+			decorator: `@Column({ type: 'vector(1536)' })`,
+			wantType:  "vector(1536)",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			col := models.InitColumn("sample", table.Name, table.Schema)
+			reader.parseColumnOptions(tt.decorator, col, table)
+
+			if col.Type != tt.wantType {
+				t.Fatalf("column type = %q, want %q", col.Type, tt.wantType)
+			}
+			if col.Length != tt.wantLength {
+				t.Fatalf("column length = %d, want %d", col.Length, tt.wantLength)
+			}
+			if col.Precision != tt.wantPrecision {
+				t.Fatalf("column precision = %d, want %d", col.Precision, tt.wantPrecision)
+			}
+			if col.Scale != tt.wantScale {
+				t.Fatalf("column scale = %d, want %d", col.Scale, tt.wantScale)
+			}
+		})
+	}
+}

pkg/writers/bun/type_mapper.go

@@ -5,6 +5,7 @@ import (
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 	"git.warky.dev/wdevs/relspecgo/pkg/writers"
 )
 
@@ -39,14 +40,7 @@ func (tm *TypeMapper) SQLTypeToGoType(sqlType string, notNull bool) string {
 
 // extractBaseType extracts the base type from a SQL type string
 func (tm *TypeMapper) extractBaseType(sqlType string) string {
-	sqlType = strings.ToLower(strings.TrimSpace(sqlType))
+	return pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
-
-	// Remove everything after '('
-	if idx := strings.Index(sqlType, "("); idx > 0 {
-		sqlType = sqlType[:idx]
-	}
-
-	return sqlType
 }
 
 // isSimpleType checks if a type should use base Go type when NOT NULL
@@ -184,9 +178,10 @@ func (tm *TypeMapper) BuildBunTag(column *models.Column, table *models.Table) st
 	if column.Type != "" {
 		// Sanitize type to remove backticks
 		typeStr := writers.SanitizeStructTagValue(column.Type)
-		if column.Length > 0 {
+		hasExplicitTypeModifier := pgsql.HasExplicitTypeModifier(typeStr)
+		if !hasExplicitTypeModifier && column.Length > 0 {
 			typeStr = fmt.Sprintf("%s(%d)", typeStr, column.Length)
-		} else if column.Precision > 0 {
+		} else if !hasExplicitTypeModifier && column.Precision > 0 {
 			if column.Scale > 0 {
 				typeStr = fmt.Sprintf("%s(%d,%d)", typeStr, column.Precision, column.Scale)
 			} else {

pkg/writers/bun/writer_test.go

@@ -698,3 +698,23 @@ func TestTypeMapper_BuildBunTag(t *testing.T) {
 		})
 	}
 }
+
+func TestTypeMapper_BuildBunTag_PreservesExplicitTypeModifiers(t *testing.T) {
+	mapper := NewTypeMapper()
+
+	col := &models.Column{
+		Name:      "embedding",
+		Type:      "vector(1536)",
+		Length:    1536,
+		Precision: 0,
+		Scale:     0,
+	}
+
+	tag := mapper.BuildBunTag(col, nil)
+	if !strings.Contains(tag, "type:vector(1536),") {
+		t.Fatalf("expected explicit modifier to be preserved, got %q", tag)
+	}
+	if strings.Contains(tag, ")(") {
+		t.Fatalf("type modifier appears duplicated in %q", tag)
+	}
+}

pkg/writers/drizzle/type_mapper.go

@@ -5,6 +5,7 @@ import (
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 )
 
 // TypeMapper handles SQL to Drizzle type conversions
@@ -18,7 +19,7 @@ func NewTypeMapper() *TypeMapper {
 // SQLTypeToDrizzle converts SQL types to Drizzle column type functions
 // Returns the Drizzle column constructor (e.g., "integer", "varchar", "text")
 func (tm *TypeMapper) SQLTypeToDrizzle(sqlType string) string {
-	sqlTypeLower := strings.ToLower(sqlType)
+	sqlTypeLower := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
 
 	// PostgreSQL type mapping to Drizzle
 	typeMap := map[string]string{
@@ -87,13 +88,6 @@ func (tm *TypeMapper) SQLTypeToDrizzle(sqlType string) string {
 		return drizzleType
 	}
 
-	// Check for partial matches (e.g., "varchar(255)" -> "varchar")
-	for sqlPattern, drizzleType := range typeMap {
-		if strings.HasPrefix(sqlTypeLower, sqlPattern) {
-			return drizzleType
-		}
-	}
-
 	// Default to text for unknown types
 	return "text"
 }

pkg/writers/gorm/type_mapper.go

@@ -5,6 +5,7 @@ import (
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 	"git.warky.dev/wdevs/relspecgo/pkg/writers"
 )
 
@@ -39,14 +40,7 @@ func (tm *TypeMapper) SQLTypeToGoType(sqlType string, notNull bool) string {
 // extractBaseType extracts the base type from a SQL type string
 // Examples: varchar(100) → varchar, numeric(10,2) → numeric
 func (tm *TypeMapper) extractBaseType(sqlType string) string {
-	sqlType = strings.ToLower(strings.TrimSpace(sqlType))
+	return pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
-
-	// Remove everything after '('
-	if idx := strings.Index(sqlType, "("); idx > 0 {
-		sqlType = sqlType[:idx]
-	}
-
-	return sqlType
 }
 
 // baseGoType returns the base Go type for a SQL type (not null)
@@ -209,9 +203,10 @@ func (tm *TypeMapper) BuildGormTag(column *models.Column, table *models.Table) s
 		// Include length, precision, scale if present
 		// Sanitize type to remove backticks
 		typeStr := writers.SanitizeStructTagValue(column.Type)
-		if column.Length > 0 {
+		hasExplicitTypeModifier := pgsql.HasExplicitTypeModifier(typeStr)
+		if !hasExplicitTypeModifier && column.Length > 0 {
 			typeStr = fmt.Sprintf("%s(%d)", typeStr, column.Length)
-		} else if column.Precision > 0 {
+		} else if !hasExplicitTypeModifier && column.Precision > 0 {
 			if column.Scale > 0 {
 				typeStr = fmt.Sprintf("%s(%d,%d)", typeStr, column.Precision, column.Scale)
 			} else {

pkg/writers/gorm/writer_test.go

@@ -669,3 +669,23 @@ func TestTypeMapper_SQLTypeToGoType(t *testing.T) {
 		})
 	}
 }
+
+func TestTypeMapper_BuildGormTag_PreservesExplicitTypeModifiers(t *testing.T) {
+	mapper := NewTypeMapper()
+
+	col := &models.Column{
+		Name:      "embedding",
+		Type:      "vector(1536)",
+		Length:    1536,
+		Precision: 0,
+		Scale:     0,
+	}
+
+	tag := mapper.BuildGormTag(col, nil)
+	if !strings.Contains(tag, "type:vector(1536)") {
+		t.Fatalf("expected explicit modifier to be preserved, got %q", tag)
+	}
+	if strings.Contains(tag, ")(") {
+		t.Fatalf("type modifier appears duplicated in %q", tag)
+	}
+}

pkg/writers/graphql/type_mapping.go

@@ -4,6 +4,7 @@ import (
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 )
 
 func (w *Writer) sqlTypeToGraphQL(sqlType string, column *models.Column, table *models.Table, schema *models.Schema) string {
@@ -33,12 +34,11 @@ func (w *Writer) sqlTypeToGraphQL(sqlType string, column *models.Column, table *
 	}
 
 	// Standard type mappings
-	baseType := strings.Split(sqlType, "(")[0] // Remove length/precision
+	baseType := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
-	baseType = strings.TrimSpace(baseType)
 
 	// Handle array types
-	if strings.HasSuffix(baseType, "[]") {
+	if pgsql.IsArrayType(sqlType) {
-		elemType := strings.TrimSuffix(baseType, "[]")
+		elemType := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(pgsql.ElementType(sqlType)))
 		gqlType := w.mapBaseTypeToGraphQL(elemType)
 		return "[" + gqlType + "]"
 	}
@@ -108,8 +108,7 @@ func (w *Writer) sqlTypeToCustomScalar(sqlType string) string {
 		"date":                     "Date",
 	}
 
-	baseType := strings.Split(sqlType, "(")[0]
+	baseType := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
-	baseType = strings.TrimSpace(baseType)
 
 	if scalar, ok := scalarMap[baseType]; ok {
 		return scalar
@@ -132,8 +131,7 @@ func (w *Writer) isIntegerType(sqlType string) bool {
 		"smallserial": true,
 	}
 
-	baseType := strings.Split(sqlType, "(")[0]
+	baseType := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
-	baseType = strings.TrimSpace(baseType)
 
 	return intTypes[baseType]
 }

pkg/writers/pgsql/writer.go

@@ -493,18 +493,19 @@ func (w *Writer) generateColumnDefinition(col *models.Column) string {
 	// Type with length/precision - convert to valid PostgreSQL type
 	baseType := pgsql.ConvertSQLType(col.Type)
 	typeStr := baseType
+	hasExplicitTypeModifier := pgsql.HasExplicitTypeModifier(baseType)
 
 	// Only add size specifiers for types that support them
-	if col.Length > 0 && col.Precision == 0 {
+	if !hasExplicitTypeModifier && col.Length > 0 && col.Precision == 0 {
-		if supportsLength(baseType) {
+		if pgsql.SupportsLength(baseType) {
 			typeStr = fmt.Sprintf("%s(%d)", baseType, col.Length)
 		} else if isTextTypeWithoutLength(baseType) {
 			// Convert text with length to varchar
 			typeStr = fmt.Sprintf("varchar(%d)", col.Length)
 		}
 		// For types that don't support length (integer, bigint, etc.), ignore the length
-	} else if col.Precision > 0 {
+	} else if !hasExplicitTypeModifier && col.Precision > 0 {
-		if supportsPrecision(baseType) {
+		if pgsql.SupportsPrecision(baseType) {
 			if col.Scale > 0 {
 				typeStr = fmt.Sprintf("%s(%d,%d)", baseType, col.Precision, col.Scale)
 			} else {
@@ -1268,30 +1269,6 @@ func isTextType(colType string) bool {
 	return false
 }
 
-// supportsLength checks if a PostgreSQL type supports length specification
-func supportsLength(colType string) bool {
-	lengthTypes := []string{"varchar", "character varying", "char", "character", "bit", "bit varying", "varbit"}
-	lowerType := strings.ToLower(colType)
-	for _, t := range lengthTypes {
-		if lowerType == t || strings.HasPrefix(lowerType, t+"(") {
-			return true
-		}
-	}
-	return false
-}
-
-// supportsPrecision checks if a PostgreSQL type supports precision/scale specification
-func supportsPrecision(colType string) bool {
-	precisionTypes := []string{"numeric", "decimal", "time", "timestamp", "timestamptz", "timestamp with time zone", "timestamp without time zone", "time with time zone", "time without time zone", "interval"}
-	lowerType := strings.ToLower(colType)
-	for _, t := range precisionTypes {
-		if lowerType == t || strings.HasPrefix(lowerType, t+"(") {
-			return true
-		}
-	}
-	return false
-}
-
 // isTextTypeWithoutLength checks if type is text (which should convert to varchar when length is specified)
 func isTextTypeWithoutLength(colType string) bool {
 	return strings.EqualFold(colType, "text")

pkg/writers/pgsql/writer_test.go

@@ -729,6 +729,56 @@ func TestColumnSizeSpecifiers(t *testing.T) {
 	}
 }
 
+func TestGenerateColumnDefinition_PreservesExplicitTypeModifiers(t *testing.T) {
+	writer := NewWriter(&writers.WriterOptions{})
+
+	cases := []struct {
+		name      string
+		colType   string
+		length    int
+		precision int
+		scale     int
+		wantType  string
+	}{
+		{
+			name:     "character varying already includes length",
+			colType:  "character varying(50)",
+			length:   50,
+			wantType: "character varying(50)",
+		},
+		{
+			name:      "numeric already includes precision",
+			colType:   "numeric(10,2)",
+			precision: 10,
+			scale:     2,
+			wantType:  "numeric(10,2)",
+		},
+		{
+			name:     "custom vector modifier preserved",
+			colType:  "vector(1536)",
+			wantType: "vector(1536)",
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			col := models.InitColumn("sample", "events", "public")
+			col.Type = tc.colType
+			col.Length = tc.length
+			col.Precision = tc.precision
+			col.Scale = tc.scale
+
+			def := writer.generateColumnDefinition(col)
+			if !strings.Contains(def, " "+tc.wantType+" ") && !strings.HasSuffix(def, " "+tc.wantType) {
+				t.Fatalf("generated definition %q does not contain expected type %q", def, tc.wantType)
+			}
+			if strings.Contains(def, ")(") {
+				t.Fatalf("generated definition %q appears to duplicate modifiers", def)
+			}
+		})
+	}
+}
+
 func TestGenerateAddColumnStatements(t *testing.T) {
 	// Create a test database with tables that have new columns
 	db := models.InitDatabase("testdb")