Drizzle ORM Schema Style Guide

Configuration

•Config: drizzle.config.ts
•Schemas: packages/database/schemas/
•Migrations: packages/database/migrations/
•Dialect: postgresql with strict: true

Helper Functions

Location: packages/database/schemas/_helpers.ts

•timestamptz(name): Timestamp with timezone
•createdAt(), updatedAt(), accessedAt(): Standard timestamp columns
•timestamps: Object with all three for easy spread

Naming Conventions

•Tables: Plural snake_case (users, session_groups)
•Columns: snake_case (user_id, created_at)

Column Definitions

Primary Keys

typescript

id: text('id')
  .primaryKey()
  .$defaultFn(() => idGenerator('agents'))
  .notNull(),

ID prefixes make entity types distinguishable. For internal tables, use uuid.

Foreign Keys

typescript

userId: text('user_id')
  .references(() => users.id, { onDelete: 'cascade' })
  .notNull(),

Timestamps

typescript

...timestamps,  // Spread from _helpers.ts

Indexes

typescript

// Return array (object style deprecated)
(t) => [uniqueIndex('client_id_user_id_unique').on(t.clientId, t.userId)],

Type Inference

typescript

export const insertAgentSchema = createInsertSchema(agents);
export type NewAgent = typeof agents.$inferInsert;
export type AgentItem = typeof agents.$inferSelect;

Example Pattern

typescript

export const agents = pgTable(
  'agents',
  {
    id: text('id')
      .primaryKey()
      .$defaultFn(() => idGenerator('agents'))
      .notNull(),
    slug: varchar('slug', { length: 100 })
      .$defaultFn(() => randomSlug(4))
      .unique(),
    userId: text('user_id')
      .references(() => users.id, { onDelete: 'cascade' })
      .notNull(),
    clientId: text('client_id'),
    chatConfig: jsonb('chat_config').$type<LobeAgentChatConfig>(),
    ...timestamps,
  },
  (t) => [uniqueIndex('client_id_user_id_unique').on(t.clientId, t.userId)],
);

Common Patterns

Junction Tables (Many-to-Many)

typescript

export const agentsKnowledgeBases = pgTable(
  'agents_knowledge_bases',
  {
    agentId: text('agent_id')
      .references(() => agents.id, { onDelete: 'cascade' })
      .notNull(),
    knowledgeBaseId: text('knowledge_base_id')
      .references(() => knowledgeBases.id, { onDelete: 'cascade' })
      .notNull(),
    userId: text('user_id')
      .references(() => users.id, { onDelete: 'cascade' })
      .notNull(),
    enabled: boolean('enabled').default(true),
    ...timestamps,
  },
  (t) => [primaryKey({ columns: [t.agentId, t.knowledgeBaseId] })],
);

Database Migrations

See references/db-migrations.md for detailed migration guide.

bash

# Generate migrations
bun run db:generate

# After modifying SQL (e.g., adding IF NOT EXISTS)
bun run db:generate:client

Migration Best Practices

sql

-- ✅ Idempotent operations
ALTER TABLE "users" ADD COLUMN IF NOT EXISTS "avatar" text;
DROP TABLE IF EXISTS "old_table";
CREATE INDEX IF NOT EXISTS "users_email_idx" ON "users" ("email");

-- ❌ Non-idempotent
ALTER TABLE "users" ADD COLUMN "avatar" text;

Rename migration files meaningfully: 0046_meaningless.sql → 0046_user_add_avatar.sql