migrate() — drizzle-orm Function Reference

Architecture documentation for the migrate() function in migrator.ts from the drizzle-orm codebase.

Function typescript DrizzleORM RelationalQuery

Entity Profile

DrizzleORM→ RelationalQuery→ migrate() — drizzle-orm Function Reference

Dependency Diagram

graph TD
  46074949_1656_64a2_a3b4_9c1f322d3998["migrate()"]
  fbe07776_671d_3f57_b962_ec600e4bdb2a["migrator.ts"]
  46074949_1656_64a2_a3b4_9c1f322d3998 -->|defined in| fbe07776_671d_3f57_b962_ec600e4bdb2a
  style 46074949_1656_64a2_a3b4_9c1f322d3998 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

drizzle-orm/src/libsql/migrator.ts lines 6–47

export async function migrate<TSchema extends Record<string, unknown>>(
	db: LibSQLDatabase<TSchema>,
	config: MigrationConfig,
) {
	const migrations = readMigrationFiles(config);
	const migrationsTable = config.migrationsTable ?? '__drizzle_migrations';

	const migrationTableCreate = sql`
		CREATE TABLE IF NOT EXISTS ${sql.identifier(migrationsTable)} (
			id SERIAL PRIMARY KEY,
			hash text NOT NULL,
			created_at numeric
		)
	`;
	await db.session.run(migrationTableCreate);

	const dbMigrations = await db.values<[number, string, string]>(
		sql`SELECT id, hash, created_at FROM ${sql.identifier(migrationsTable)} ORDER BY created_at DESC LIMIT 1`,
	);

	const lastDbMigration = dbMigrations[0] ?? undefined;

	const statementToBatch = [];

	for (const migration of migrations) {
		if (!lastDbMigration || Number(lastDbMigration[2])! < migration.folderMillis) {
			for (const stmt of migration.sql) {
				statementToBatch.push(db.run(sql.raw(stmt)));
			}

			statementToBatch.push(
				db.run(
					sql`INSERT INTO ${
						sql.identifier(migrationsTable)
					} ("hash", "created_at") VALUES(${migration.hash}, ${migration.folderMillis})`,
				),
			);
		}
	}

	await db.session.migrate(statementToBatch);
}