d1

@workkit/d1

Typed D1 client with query builder, column transforms, and classified errors

Install

bun add @workkit/d1

Usage

Before (raw D1 API)

// Verbose prepared statements, manual snake_case conversion, generic errors
const stmt = env.DB.prepare("SELECT * FROM users WHERE id = ?").bind(id)
const result = await stmt.first()
const user = result as any // hope for the best
// result.created_at — stuck with snake_case from DB

// Errors are generic — was it a constraint violation? A syntax error?
try {
  await env.DB.prepare("INSERT INTO users (id) VALUES (?)").bind(id).run()
} catch (e) {
  // "D1_ERROR" — thanks, very helpful
}

After (workkit d1)

import { d1 } from "@workkit/d1"

const db = d1(env.DB, { transformColumns: "camelCase" })

// Simple queries
const user = await db.first<User>("SELECT * FROM users WHERE id = ?", [id])
// user.createdAt — auto-transformed to camelCase

// Fluent query builder
const admins = await db
  .select<User>("users")
  .where("role = ?", ["admin"])
  .orderBy("created_at", "DESC")
  .limit(10)
  .all()

// Insert with returning
const newUser = await db
  .insert("users")
  .values({ id: "123", name: "Alice", role: "admin" })
  .returning<User>()

// Classified errors
try {
  await db.insert("users").values({ id: "123" }).run()
} catch (e) {
  if (e instanceof D1ConstraintError) {
    // UNIQUE constraint failed — handle specifically
  }
}

API

d1(binding, options?)

Create a typed D1 client.

Options:

• transformColumns — "camelCase" or a custom (column: string) => string function
• logQueries — Log SQL to console (default: false)

Query Methods:

• first<T>(sql, params?) — Get first row or null
• all<T>(sql, params?) — Get all rows
• run(sql, params?) — Execute a write query, returns D1RunResult
• exec(sql) — Execute raw SQL (multiple statements)
• batch(statements) — Execute multiple statements atomically
• prepare(sql) — Create a typed prepared statement

Query Builder:

• select<T>(table) — .where(), .orderBy(), .limit(), .offset(), .all(), .first()
• insert(table) — .values(), .onConflict(), .returning(), .run()
• update(table) — .set(), .where(), .returning(), .run()
• delete(table) — .where(), .returning(), .run()

Error Classes

• D1QueryError — SQL syntax or execution errors
• D1ConstraintError — UNIQUE/FOREIGN KEY/CHECK constraint violations
• D1BatchError — Batch execution failures
• D1MigrationError — Migration-specific errors
• classifyD1Error(err) — Classify raw D1 errors into typed classes

License

MIT