pkg/inspector/README.md

@@ -123,6 +123,7 @@ rules:
 | `missing_primary_key` | `have_primary_key` | Ensure tables have primary keys |
 | `orphaned_foreign_key` | `orphaned_foreign_key` | Detect FKs referencing non-existent tables |
 | `circular_dependency` | `circular_dependency` | Detect circular FK dependencies |
+| `duplicate_index_name` | `duplicate_index_name` | Index / PK / unique names must be unique per schema (default: `enforce`) |
 
 ## Rule Configuration
 

pkg/inspector/inspector.go

@@ -161,6 +161,7 @@ func getValidator(functionName string) (validatorFunc, bool) {
 		"have_primary_key":              validateMissingPrimaryKey,
 		"orphaned_foreign_key":          validateOrphanedForeignKey,
 		"circular_dependency":           validateCircularDependency,
+		"duplicate_index_name":          validateDuplicateIndexName,
 	}
 
 	fn, exists := validators[functionName]

pkg/inspector/rules.go

@@ -154,6 +154,11 @@ func GetDefaultConfig() *Config {
 				Function: "circular_dependency",
 				Message:  "Circular foreign key dependency detected",
 			},
+			"duplicate_index_name": {
+				Enabled:  "enforce",
+				Function: "duplicate_index_name",
+				Message:  "Index name is reused within the schema; PostgreSQL skips the duplicate CREATE INDEX IF NOT EXISTS",
+			},
 		},
 	}
 }

pkg/inspector/rules_test.go

@@ -37,6 +37,7 @@ func TestGetDefaultConfig(t *testing.T) {
 		"missing_primary_key",
 		"orphaned_foreign_key",
 		"circular_dependency",
+		"duplicate_index_name",
 	}
 
 	for _, ruleName := range expectedRules {

pkg/inspector/validators.go

@@ -643,3 +643,64 @@ func contains(slice []string, value string) bool {
 	}
 	return false
 }
+
+// validateDuplicateIndexName checks that index names are unique per schema.
+// PostgreSQL keeps indexes in the schema-wide relation namespace, so a name
+// reused on another table makes CREATE INDEX IF NOT EXISTS silently skip it.
+// Primary key and unique constraints create backing indexes and share that
+// namespace too. An index and a constraint with the same name on the same
+// table describe one object and are not reported.
+func validateDuplicateIndexName(db *models.Database, rule Rule, ruleName string) []ValidationResult {
+	results := []ValidationResult{}
+
+	for _, schema := range db.Schemas {
+		// lowercased name -> "table" entries, one per distinct object
+		owners := make(map[string][]string)
+		display := make(map[string]string)
+		order := []string{}
+
+		add := func(name, table string, sameTableMerges bool) {
+			key := strings.ToLower(name)
+			if _, seen := owners[key]; !seen {
+				order = append(order, key)
+				display[key] = name
+			}
+			if sameTableMerges && contains(owners[key], table) {
+				return
+			}
+			owners[key] = append(owners[key], table)
+		}
+
+		for _, table := range schema.Tables {
+			for _, key := range sortedKeys(table.Indexes) {
+				if name := table.Indexes[key].Name; name != "" {
+					add(name, table.Name, false)
+				}
+			}
+			for _, c := range sortConstraints(table.Constraints) {
+				if c.Name == "" || (c.Type != models.PrimaryKeyConstraint && c.Type != models.UniqueConstraint) {
+					continue
+				}
+				add(c.Name, table.Name, true)
+			}
+		}
+
+		for _, key := range order {
+			tables := owners[key]
+			results = append(results, createResult(
+				ruleName,
+				len(tables) == 1,
+				rule.Message,
+				formatLocation(schema.Name, display[key], "")+" on "+strings.Join(tables, ", "),
+				map[string]interface{}{
+					"schema":      schema.Name,
+					"index":       display[key],
+					"tables":      tables,
+					"occurrences": len(tables),
+				},
+			))
+		}
+	}
+
+	return results
+}

pkg/inspector/validators_test.go

@@ -835,3 +835,84 @@ func TestFormatLocation(t *testing.T) {
 		})
 	}
 }
+
+func TestValidateDuplicateIndexName(t *testing.T) {
+	db := &models.Database{
+		Name: "testdb",
+		Schemas: []*models.Schema{
+			{
+				Name: "entity",
+				Tables: []*models.Table{
+					{
+						Name: "actor_phone",
+						Indexes: map[string]*models.Index{
+							"idx_actor": {Name: "idx_actor", Columns: []string{"rid_actor"}},
+							"uk_phone":  {Name: "uk_phone", Columns: []string{"phone"}, Unique: true},
+						},
+						Constraints: map[string]*models.Constraint{
+							// Same name as the index on the same table: one object.
+							"uk_phone": {Name: "uk_phone", Type: models.UniqueConstraint, Columns: []string{"phone"}},
+						},
+					},
+					{
+						Name: "actor_email",
+						Indexes: map[string]*models.Index{
+							"idx_actor": {Name: "idx_actor", Columns: []string{"rid_actor"}},
+						},
+						Constraints: map[string]*models.Constraint{
+							"UK_Phone": {Name: "UK_Phone", Type: models.UniqueConstraint, Columns: []string{"email"}},
+						},
+					},
+					{
+						Name: "actor_address",
+						Indexes: map[string]*models.Index{
+							"idx_actor":   {Name: "idx_actor", Columns: []string{"rid_actor"}},
+							"idx_actor#2": {Name: "idx_actor", Columns: []string{"rid_actor", "kind"}},
+							"idx_address": {Name: "idx_address", Columns: []string{"line1"}},
+						},
+					},
+				},
+			},
+			{
+				// Same names in another schema do not collide.
+				Name: "org",
+				Tables: []*models.Table{
+					{Name: "api_provider", Indexes: map[string]*models.Index{"idx_actor": {Name: "idx_actor"}}},
+				},
+			},
+		},
+	}
+
+	results := validateDuplicateIndexName(db, Rule{Message: "dup"}, "duplicate_index_name")
+
+	got := map[string]bool{}
+	occ := map[string]int{}
+	for _, r := range results {
+		key := r.Context["schema"].(string) + "." + r.Context["index"].(string)
+		got[key] = r.Passed
+		occ[key] = r.Context["occurrences"].(int)
+	}
+
+	want := map[string]struct {
+		passed bool
+		occ    int
+	}{
+		"entity.idx_actor":   {false, 4},
+		"entity.uk_phone":    {false, 2},
+		"entity.idx_address": {true, 1},
+		"org.idx_actor":      {true, 1},
+	}
+	if len(got) != len(want) {
+		t.Fatalf("got %d results %v, want %d", len(got), got, len(want))
+	}
+	for k, w := range want {
+		p, ok := got[k]
+		if !ok {
+			t.Errorf("missing result for %s", k)
+			continue
+		}
+		if p != w.passed || occ[k] != w.occ {
+			t.Errorf("%s: passed=%v occurrences=%d, want passed=%v occurrences=%d", k, p, occ[k], w.passed, w.occ)
+		}
+	}
+}