docs: improve migration with Drizzle ORM

Author: atinux

docs/content/docs/3.recipes/2.drizzle.md

@@ -110,26 +110,38 @@ export default defineNitroPlugin(async () => {
 
     const database = hubDatabase()
 
-    for (const file of migrationFiles) {
+    // Make sure to create the _hub_migrations table if it doesn't exist
+    await database.prepare('CREATE TABLE IF NOT EXISTS _hub_migrations (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT NOT NULL, created_at INTEGER NOT NULL)').run()
+
+    // Get applied migrations from database
+    const hubMigrations = await database.prepare('SELECT * FROM _hub_migrations').all()
+    const appliedMigrations = (hubMigrations.results || []).map((row) => row.name)
+    const missingMigrations = migrationFiles.filter(file => !appliedMigrations.includes(file))
+    if (!missingMigrations.length) {
+      consola.success('Database up-to-date and ready')
+      return
+    }
+
+    // Apply missing migrations
+    const appliedMigrationsStmts = []
+    for (const file of missingMigrations) {
       consola.info(`Applying database migrations from ${file}...`)
       const migration = (await migrationsStorage.getItem<string>(file)) || ''
       const statements = migration.split('--> statement-breakpoint')
       for (let stmt of statements) {
-        stmt = stmt
-          .trim()
-          .replace('CREATE TABLE', 'CREATE TABLE IF NOT EXISTS')
-          .replace('CREATE INDEX', 'CREATE INDEX IF NOT EXISTS')
-          .replace('CREATE UNIQUE INDEX', 'CREATE UNIQUE INDEX IF NOT EXISTS')
-        await database.prepare(stmt).run()
+        await database.prepare(stmt.trim()).run()
       }
+      appliedMigrationsStmts.push(database.prepare('INSERT INTO _hub_migrations (name, created_at) VALUES (?, ?)').bind(file, Date.now()))
     }
+    await database.batch(appliedMigrationsStmts)
     consola.success('Database migrations done')
   })
 })
+
 ```
 
 ::callout
-This solution is not perfect as it will run the migrations every time the server starts. You can improve it by keeping track of the migrations that have been applied and only run the new ones.
+This solution is will create a `_hub_migrations` table in your database to keep track of the applied migrations. It will also run the migrations automatically in development mode.
 ::
 
 ### `useDrizzle()`