Export more precise typings for data types. Expose the database error so that users can use instanceof checks

Author: jacobdr

src/constants.ts

@@ -130,7 +130,9 @@ export const DataTypeOIDs = {
   _varbit: 1563,
   _uuid: 2951,
   _jsonb: 3807,
-};
+} as const;
+
+type INumericDataTypes = (typeof DataTypeOIDs)[keyof typeof DataTypeOIDs];
 
 export const DataTypeNames = {
   [DataTypeOIDs.bool]: 'bool',
@@ -247,4 +249,6 @@ export const DataTypeNames = {
   [DataTypeOIDs._varbit]: '_varbit',
   [DataTypeOIDs._uuid]: '_uuid',
   [DataTypeOIDs._jsonb]: '_jsonb',
+} as const satisfies {
+  [key in INumericDataTypes]: string;
 };

src/index.ts

@@ -1,3 +1,5 @@
+export { DatabaseError } from './protocol/database-error.js';
+
 export * from './constants.js';
 export * from './data-type-map.js';
 export * from './types.js';