@xemahq/app-schema-ddl

Compile typed schema change plans into Postgres DDL

Overview

Turns a typed SchemaChangePlan into Postgres DDL statements. Callers send a plan, never SQL. Column types come from a closed set (PgTypeToken), and every identifier is validated against KEY_PATTERN before it is quoted. The additive compiler cannot emit a DROP; destructive changes go through a separate compiler.

When to use it

• You generate or apply schema changes for app entity tables and want one auditable SQL emitter.

Installation

pnpm add @xemahq/app-schema-ddl

Usage

import {
  AppSchemaChangeKind,
  PgTypeToken,
  compileAdditivePlan,
} from '@xemahq/app-schema-ddl';

const statements = compileAdditivePlan({
  schemaName: 'shop',
  changes: [
    {
      kind: AppSchemaChangeKind.AddEntity,
      entityKey: 'order',
      columns: [{ key: 'total', type: PgTypeToken.DoublePrecision, notNull: true }],
    },
  ],
});

compileDestructivePlan(plan) handles renames, narrowing and drops. Invalid input throws AppSchemaDdlError.

License

Apache-2.0 © Xema — xema.dev