pg_type index implementation

server/tables/pgcatalog/pg_catalog_cache.go

@@ -24,7 +24,6 @@ import (
 	"github.com/dolthub/doltgresql/core/id"
 	"github.com/dolthub/doltgresql/core/sequences"
 	"github.com/dolthub/doltgresql/server/functions"
-	pgtypes "github.com/dolthub/doltgresql/server/types"
 )
 
 // pgNamespace represents a row in the pg_namespace table.
@@ -48,6 +47,9 @@ type pgCatalogCache struct {
 	// pg_classes
 	pgClasses *pgClassCache
 
+	// pg_type
+	pgTypes *pgTypeCache
+
 	// pg_constraints
 	pgConstraints *pgConstraintCache
 
@@ -72,10 +74,6 @@ type pgCatalogCache struct {
 	views       []sql.ViewDefinition
 	viewSchemas []string
 
-	// pg_types
-	types        []*pgtypes.DoltgresType
-	schemasToOid map[string]id.Namespace
-
 	// pg_tables
 	tables       []sql.Table
 	systemTables []doltdb.TableName
@@ -103,6 +101,28 @@ func (p pgClassCache) getIndex(name string) *inMemIndexStorage[*pgClass] {
 
 var _ BTreeStorageAccess[*pgClass] = &pgClassCache{}
 
+// pgTypeCache holds cached data for the pg_type table, including two btree indexes for fast lookups by OID and
+// by typname
+type pgTypeCache struct {
+	types   []*pgType
+	nameIdx *inMemIndexStorage[*pgType]
+	oidIdx  *inMemIndexStorage[*pgType]
+}
+
+// getIndex implements BTreeStorageAccess.
+func (p pgTypeCache) getIndex(name string) *inMemIndexStorage[*pgType] {
+	switch name {
+	case PgTypeOidIndex:
+		return p.oidIdx
+	case PgTypnameIndex:
+		return p.nameIdx
+	default:
+		panic("unknown pg_type index: " + name)
+	}
+}
+
+var _ BTreeStorageAccess[*pgType] = &pgTypeCache{}
+
 // pgIndexCache holds cached data for the pg_index table, including two btree indexes for fast lookups by index OID
 type pgIndexCache struct {
 	indexes     []*pgIndex