fix: support CHECK constraints without columns and NO INHERIT modifier (#386)

internal/diff/constraint.go

@@ -72,10 +72,13 @@ func generateConstraintSQL(constraint *ir.Constraint, targetSchema string) strin
 		}
 		return stmt
 	case ir.ConstraintTypeCheck:
-		// Generate CHECK constraint with proper NOT VALID placement
-		// The CheckClause is normalized to exclude NOT VALID (stripped in normalize.go)
-		// We append NOT VALID based on IsValid field, mimicking pg_dump behavior
+		// Generate CHECK constraint with proper NOT VALID / NO INHERIT placement
+		// The CheckClause is normalized to exclude NOT VALID and NO INHERIT (stripped in normalize.go)
+		// We append them based on IsValid/NoInherit fields, mimicking pg_dump behavior
 		result := fmt.Sprintf("CONSTRAINT %s %s", ir.QuoteIdentifier(constraint.Name), constraint.CheckClause)
+		if constraint.NoInherit {
+			result += " NO INHERIT"
+		}
 		if !constraint.IsValid {
 			result += " NOT VALID"
 		}
@@ -150,6 +153,9 @@ func constraintsEqual(old, new *ir.Constraint) bool {
 	if old.CheckClause != new.CheckClause {
 		return false
 	}
+	if old.NoInherit != new.NoInherit {
+		return false
+	}
 	if old.ExclusionDefinition != new.ExclusionDefinition {
 		return false
 	}

internal/diff/table.go

@@ -892,8 +892,12 @@ func (td *tableDiff) generateAlterTableStatements(targetSchema string, collector
 			// Ensure CHECK clause has outer parentheses around the full expression
 			tableName := getTableNameWithSchema(td.Table.Schema, td.Table.Name, targetSchema)
 			clause := ensureCheckClauseParens(constraint.CheckClause)
-			canonicalSQL := fmt.Sprintf("ALTER TABLE %s\nADD CONSTRAINT %s %s;",
-				tableName, ir.QuoteIdentifier(constraint.Name), clause)
+			suffix := ""
+			if constraint.NoInherit {
+				suffix += " NO INHERIT"
+			}
+			canonicalSQL := fmt.Sprintf("ALTER TABLE %s\nADD CONSTRAINT %s %s%s;",
+				tableName, ir.QuoteIdentifier(constraint.Name), clause, suffix)
 
 			context := &diffContext{
 				Type:                DiffTypeTableConstraint,
@@ -1005,8 +1009,12 @@ func (td *tableDiff) generateAlterTableStatements(targetSchema string, collector
 
 		case ir.ConstraintTypeCheck:
 			// Add CHECK constraint with ensured outer parentheses
-			addSQL = fmt.Sprintf("ALTER TABLE %s\nADD CONSTRAINT %s %s;",
-				tableName, ir.QuoteIdentifier(constraint.Name), ensureCheckClauseParens(constraint.CheckClause))
+			suffix := ""
+			if constraint.NoInherit {
+				suffix += " NO INHERIT"
+			}
+			addSQL = fmt.Sprintf("ALTER TABLE %s\nADD CONSTRAINT %s %s%s;",
+				tableName, ir.QuoteIdentifier(constraint.Name), ensureCheckClauseParens(constraint.CheckClause), suffix)
 
 		case ir.ConstraintTypeForeignKey:
 			// Sort columns by position

internal/plan/rewrite.go

@@ -210,8 +210,12 @@ func generateIndexChangeRewrite(indexDiff *diff.IndexDiff) []RewriteStep {
 func generateConstraintRewrite(constraint *ir.Constraint) []RewriteStep {
 	tableName := getTableNameWithSchema(constraint.Schema, constraint.Table)
 
-	notValidSQL := fmt.Sprintf("ALTER TABLE %s\nADD CONSTRAINT %s %s NOT VALID;",
-		tableName, ir.QuoteIdentifier(constraint.Name), constraint.CheckClause)
+	noInheritSuffix := ""
+	if constraint.NoInherit {
+		noInheritSuffix = " NO INHERIT"
+	}
+	notValidSQL := fmt.Sprintf("ALTER TABLE %s\nADD CONSTRAINT %s %s%s NOT VALID;",
+		tableName, ir.QuoteIdentifier(constraint.Name), constraint.CheckClause, noInheritSuffix)
 	validateSQL := fmt.Sprintf("ALTER TABLE %s VALIDATE CONSTRAINT %s;",
 		tableName, ir.QuoteIdentifier(constraint.Name))
 

ir/inspector.go

@@ -453,7 +453,11 @@ func (i *Inspector) buildConstraints(ctx context.Context, schema *IR, targetSche
 		}
 
 		if columnName == "" || columnName == "<nil>" {
-			continue // Skip constraints without columns
+			// CHECK and EXCLUDE constraints may have no columns (e.g., CHECK (FALSE))
+			// Only skip non-CHECK/EXCLUDE constraints without columns
+			if constraintType != "CHECK" && constraintType != "EXCLUDE" {
+				continue
+			}
 		}
 
 		key := constraintKey{
@@ -487,6 +491,7 @@ func (i *Inspector) buildConstraints(ctx context.Context, schema *IR, targetSche
 				Name:       constraintName,
 				Type:       cType,
 				Columns:    []*ConstraintColumn{},
+				NoInherit:  constraint.NoInherit,
 				IsTemporal: constraint.IsPeriod, // PG18 temporal constraint (WITHOUT OVERLAPS / PERIOD)
 			}
 
@@ -537,52 +542,55 @@ func (i *Inspector) buildConstraints(ctx context.Context, schema *IR, targetSche
 			constraintGroups[key] = c
 		}
 
-		// Get column position in constraint
-		position := i.getConstraintColumnPosition(ctx, schemaName, constraintName, columnName)
+		// Add column to constraint (skip for column-less constraints like CHECK (FALSE))
+		if columnName != "" && columnName != "<nil>" {
+			// Get column position in constraint
+			position := i.getConstraintColumnPosition(ctx, schemaName, constraintName, columnName)
 
-		// Check if column already exists in constraint to avoid duplicates
-		columnExists := false
-		for _, existingCol := range c.Columns {
-			if existingCol.Name == columnName {
-				columnExists = true
-				break
+			// Check if column already exists in constraint to avoid duplicates
+			columnExists := false
+			for _, existingCol := range c.Columns {
+				if existingCol.Name == columnName {
+					columnExists = true
+					break
+				}
 			}
-		}
 
-		// Add column to constraint only if it doesn't exist
-		if !columnExists {
-			constraintCol := &ConstraintColumn{
-				Name:     columnName,
-				Position: position,
+			// Add column to constraint only if it doesn't exist
+			if !columnExists {
+				constraintCol := &ConstraintColumn{
+					Name:     columnName,
+					Position: position,
+				}
+				c.Columns = append(c.Columns, constraintCol)
 			}
-			c.Columns = append(c.Columns, constraintCol)
-		}
-
-		// Handle foreign key referenced columns
-		if c.Type == ConstraintTypeForeignKey {
-			if refColumnName := i.safeInterfaceToString(constraint.ForeignColumnName); refColumnName != "" && refColumnName != "<nil>" {
-				// Check if referenced column already exists to avoid duplicates
-				refColumnExists := false
-				for _, existingRefCol := range c.ReferencedColumns {
-					if existingRefCol.Name == refColumnName {
-						refColumnExists = true
-						break
+
+			// Handle foreign key referenced columns
+			if c.Type == ConstraintTypeForeignKey {
+				if refColumnName := i.safeInterfaceToString(constraint.ForeignColumnName); refColumnName != "" && refColumnName != "<nil>" {
+					// Check if referenced column already exists to avoid duplicates
+					refColumnExists := false
+					for _, existingRefCol := range c.ReferencedColumns {
+						if existingRefCol.Name == refColumnName {
+							refColumnExists = true
+							break
+						}
 					}
-				}
 
-				// Add referenced column only if it doesn't exist
-				if !refColumnExists {
-					// Use the local column's constraint position for the referenced column.
-					// The local and referenced columns are paired together in the FK definition,
-					// so they must have the same position to maintain correct ordering.
-					// Note: ForeignOrdinalPosition from the query is fa.attnum (column position
-					// in the foreign table's definition), which is wrong - we need the constraint
-					// array position, which is the same as the local column's position.
-					refConstraintCol := &ConstraintColumn{
-						Name:     refColumnName,
-						Position: position, // Use local column's constraint position
+					// Add referenced column only if it doesn't exist
+					if !refColumnExists {
+						// Use the local column's constraint position for the referenced column.
+						// The local and referenced columns are paired together in the FK definition,
+						// so they must have the same position to maintain correct ordering.
+						// Note: ForeignOrdinalPosition from the query is fa.attnum (column position
+						// in the foreign table's definition), which is wrong - we need the constraint
+						// array position, which is the same as the local column's position.
+						refConstraintCol := &ConstraintColumn{
+							Name:     refColumnName,
+							Position: position, // Use local column's constraint position
+						}
+						c.ReferencedColumns = append(c.ReferencedColumns, refConstraintCol)
 					}
-					c.ReferencedColumns = append(c.ReferencedColumns, refConstraintCol)
 				}
 			}
 		}

ir/ir.go

@@ -222,6 +222,7 @@ type Constraint struct {
 	Deferrable          bool                `json:"deferrable,omitempty"`
 	InitiallyDeferred   bool                `json:"initially_deferred,omitempty"`
 	IsValid             bool                `json:"is_valid,omitempty"`
+	NoInherit           bool                `json:"no_inherit,omitempty"` // CHECK constraint NO INHERIT modifier
 	IsTemporal          bool                `json:"is_temporal,omitempty"` // PG18: temporal constraint (WITHOUT OVERLAPS on PK/UNIQUE, PERIOD on FK)
 	Comment             string              `json:"comment,omitempty"`
 }

ir/normalize.go

@@ -1158,6 +1158,8 @@ func normalizeConstraint(constraint *Constraint) {
 	// Only normalize CHECK and EXCLUDE constraints - other constraint types are already consistent
 	if constraint.Type == ConstraintTypeCheck && constraint.CheckClause != "" {
 		constraint.CheckClause = normalizeCheckClause(constraint.CheckClause)
+		// pg_get_constraintdef may include NO INHERIT suffix — strip it and use the NoInherit field instead
+		// (NoInherit is already set from connoinherit in the query)
 	}
 	if constraint.Type == ConstraintTypeExclusion && constraint.ExclusionDefinition != "" {
 		constraint.ExclusionDefinition = normalizeExclusionDefinition(constraint.ExclusionDefinition)
@@ -1179,10 +1181,14 @@ func normalizeExclusionDefinition(definition string) string {
 // now come from the same PostgreSQL version via pg_get_constraintdef(), they produce identical
 // output. We only need basic cleanup for PostgreSQL internal representations.
 func normalizeCheckClause(checkClause string) string {
-	// Strip " NOT VALID" suffix if present (mimicking pg_dump behavior)
-	// PostgreSQL's pg_get_constraintdef may include NOT VALID at the end,
-	// but we want to control its placement via the IsValid field
+	// Strip " NOT VALID" and " NO INHERIT" suffixes if present
+	// PostgreSQL's pg_get_constraintdef may include these at the end,
+	// but we control their placement via the IsValid and NoInherit fields
 	clause := strings.TrimSpace(checkClause)
+	if strings.HasSuffix(clause, " NO INHERIT") {
+		clause = strings.TrimSuffix(clause, " NO INHERIT")
+		clause = strings.TrimSpace(clause)
+	}
 	if strings.HasSuffix(clause, " NOT VALID") {
 		clause = strings.TrimSuffix(clause, " NOT VALID")
 		clause = strings.TrimSpace(clause)

ir/queries/queries.sql

@@ -338,7 +338,8 @@ SELECT
     c.condeferrable AS deferrable,
     c.condeferred AS initially_deferred,
     c.convalidated AS is_valid,
-    COALESCE((to_jsonb(c) ->> 'conperiod')::boolean, false) AS is_period
+    COALESCE((to_jsonb(c) ->> 'conperiod')::boolean, false) AS is_period,
+    c.connoinherit AS no_inherit
 FROM pg_constraint c
 JOIN pg_class cl ON c.conrelid = cl.oid
 JOIN pg_namespace n ON cl.relnamespace = n.oid
@@ -917,7 +918,8 @@ SELECT
     c.condeferrable AS deferrable,
     c.condeferred AS initially_deferred,
     c.convalidated AS is_valid,
-    COALESCE((to_jsonb(c) ->> 'conperiod')::boolean, false) AS is_period
+    COALESCE((to_jsonb(c) ->> 'conperiod')::boolean, false) AS is_period,
+    c.connoinherit AS no_inherit
 FROM pg_constraint c
 JOIN pg_class cl ON c.conrelid = cl.oid
 JOIN pg_namespace n ON cl.relnamespace = n.oid

testdata/diff/comment/add_column_comments/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "395a31ea82eaee99933280fdb3f320487dd7dabef2dd772729c7e5f3b8ceff9e"
+    "hash": "1351e4ca7db945af39a49da2b23273d5b33a8b1b9bd3b6a45f3cb4cf2cfce1a2"
   },
   "groups": [
     {

testdata/diff/comment/add_index_comment/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "d5424ad774c4a220725ab96071453230e0817f6ed77df1c3d427be4c28d1d3e5"
+    "hash": "a859ebafe82f0638592346ffb79d2bb11c1f0748d86308a87ff66c51abb68592"
   },
   "groups": [
     {

testdata/diff/comment/add_table_comment/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "ecf6d758d162c619907a2ab40f21478757d500dcc5885194afc013992e700339"
+    "hash": "f2623b8934b586c1ae51649bdfdcc295015334ce0d0cd6b7f4d6e2bc077030b3"
   },
   "groups": [
     {

testdata/diff/comment/alter_table_comment/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "8a4456790d31384951589e1a5cfcdb72c2c13db9aa651fa67f69dd210a4df0f5"
+    "hash": "1f242a84c8de680321c9fc75dcc5a06760ac51cc74d2e6b6affe524e341745f9"
   },
   "groups": [
     {

testdata/diff/comment/drop_table_comment/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "22213fffa77d3732ce0dd017e5f6f54c8c1da4c2b052a2c82e06a119a491614f"
+    "hash": "2ae68cfa8f7248d127b54e8c0ba366176b4e6ba698ed57883686f134a287ef16"
   },
   "groups": [
     {

testdata/diff/comment/mixed_comments/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "4f1b7baaff86b8f65e5ed747a064727e12fb0aeedff84f6f74439d1e20759dad"
+    "hash": "84e9a9b7c080fc6d686f528f11d070d030b1ab82e66a2ad98050868d66d2f98a"
   },
   "groups": [
     {

testdata/diff/comment/noop_column_comments/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "0f6266823ea77f5c0d7e8fe9d4b61bc9a40e38d6e25e26dfdf99944e5c4be0d9"
+    "hash": "06d2c3351398ca9ab591c3985cf2791ac3ff5b960eadac98470abbc0b611734a"
   },
   "groups": null
 }

testdata/diff/create_function/issue_354_empty_search_path/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "742d612cedabf2d80d87df6c7d9fac8911e008b29ef8e15d16a32d2edf43ddd9"
+    "hash": "29f02983bf9ecf6f5f1ec38377f7209ec60f4fe4051d371227ace7d93bddf381"
   },
   "groups": [
     {

testdata/diff/create_materialized_view/add_materialized_view/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "f787a47486736a59da932aa3fc0cb21e0fc423cfa56d1b2d3de2b529ccae64b9"
+    "hash": "c080880eeed5c864d9039e5087e56335177c19b37ace103267da30a2ef36775b"
   },
   "groups": [
     {

testdata/diff/create_materialized_view/alter_materialized_view/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "f0ac3bb964fd207775142c2f9119442b29f04e10c74de4162cf6e468335e5835"
+    "hash": "d7265cc266dac8551a3b9f37cf2293f45c601b13dafb6bb301915976389a3927"
   },
   "groups": [
     {

testdata/diff/create_materialized_view/drop_materialized_view/plan.json

@@ -3,7 +3,7 @@
   "pgschema_version": "1.8.0",
   "created_at": "1970-01-01T00:00:00Z",
   "source_fingerprint": {
-    "hash": "6ab6529bbf7c84fb6b639938bdaa3ca5af18b75b3de3637421b43469e4342865"
+    "hash": "a90a90090750b18a9aaffb6de253bd12234fe30ccf9cfc35b82c34ac834f1360"
   },
   "groups": [
     {