interface

ReservedSQL

interface ReservedSQL

A connection reserved from the pool with SQL.reserve. Call release to return it to the pool.

After release(), a query on this client that has not started rejects with ERR_POSTGRES_CONNECTION_CLOSED or ERR_MYSQL_CONNECTION_CLOSED. Queries are lazy, so this includes a query that a using block returns without await.

  • options: Merge<SQLiteOptions, PostgresOrMySQLOptions> | Merge<PostgresOrMySQLOptions, SQLiteOptions>

    The resolved settings of the client, after the URL, the options and the environment are merged.

    Treat it as output. Timeouts are in milliseconds here, and only the long option names are set (hostname, not host), so new SQL(sql.options) does not make an equal client. console.log prints [REDACTED] for the password and the TLS key.

  • [Symbol.asyncDispose](): PromiseLike<void>;
  • values: any[] | TypedArray<ArrayBufferLike>,
    typeNameOrTypeID?: number | ArrayType

    Creates a PostgreSQL array parameter. null elements are SQL NULL, and nested arrays make a multi-dimensional array. Throws on MySQL and SQLite.

    @param values

    Array values to bind

    @param typeNameOrTypeID

    Element type name, or the OID of the array type. Bun casts the parameter to it: $1::INT[]. When omitted, Bun adds no cast and the server infers the type from the column, the compared value or a cast in the query. Pass it when the query gives no context: a bare SELECT ${sql.array([1])} returns the text {"1"}. Pass "JSON" or "JSONB" to encode each element as JSON: there null is the JSON value null, undefined is SQL NULL, and sql.json([1, 2]) stores a JSON array as one element.

    @returns

    The array parameter, ready to interpolate into a query

    const array = sql.array([1, 2, 3], "INT");
    await sql`CREATE TABLE users_posts (user_id INT, posts_id INT[])`;
    await sql`INSERT INTO users_posts (user_id, posts_id) VALUES (${user.id}, ${array})`;
    
    // the server infers the type from the compared column
    await sql`SELECT * FROM users WHERE id = ANY(${sql.array([1, 2, 3])})`;
  • begin<T>(
    ): Promise<ContextCallbackResult<T>>;

    Begins a new transaction.

    Reserves a connection for the transaction and passes a scoped sql instance to the callback. sql.begin resolves with the callback's return value. BEGIN is sent automatically, and if anything fails, ROLLBACK is sent so the connection can be released and execution can continue.

    const [user, account] = await sql.begin(async sql => {
      const [user] = await sql`
        insert into users (
          name
        ) values (
          'Murray'
        )
        returning *
      `
      const [account] = await sql`
        insert into accounts (
          user_id
        ) values (
          ${ user.user_id }
        )
        returning *
      `
      return [user, account]
    })
    begin<T>(
    options: string,
    ): Promise<ContextCallbackResult<T>>;

    Begins a new transaction with options.

    Reserves a connection for the transaction and passes a scoped sql instance to the callback. sql.begin resolves with the callback's return value. BEGIN is sent with the given options, and if anything fails, ROLLBACK is sent so the connection can be released and execution can continue.

    const [user, account] = await sql.begin("read write", async sql => {
      const [user] = await sql`
        insert into users (
          name
        ) values (
          'Murray'
        )
        returning *
      `
      const [account] = await sql`
        insert into accounts (
          user_id
        ) values (
          ${ user.user_id }
        )
        returning *
      `
      return [user, account]
    })
  • name: string,
    ): Promise<ContextCallbackResult<T>>;

    Begins a distributed transaction, also known as Two-Phase Commit. In phase 1 the coordinator prepares each node, making sure its data is written and ready to commit; in phase 2 the nodes commit or roll back based on the coordinator's decision, ensuring durability and releasing locks.

    beginDistributed rolls back automatically if an exception is not caught; otherwise you commit or roll back later with commitDistributed or rollbackDistributed.

    In PostgreSQL and MySQL, distributed transactions persist beyond the original session, so privileged users or coordinators can commit or roll them back later, which supports recovery and administrative tasks. PostgreSQL implements them with PREPARE TRANSACTION; MySQL uses XA Transactions. MSSQL also supports distributed/XA transactions, but ties them to the original session, the DTC coordinator, and the specific connection: they are committed or rolled back under the same rules as regular transactions, with no manual intervention from other sessions, and are used to coordinate transactions across Linked Servers.

    await sql.beginDistributed("numbers", async sql => {
      await sql`create table if not exists numbers (a int)`;
      await sql`insert into numbers values(1)`;
    });
    // later you can call
    await sql.commitDistributed("numbers");
    // or await sql.rollbackDistributed("numbers");
  • options?: { timeout: number }
    ): Promise<void>;

    Closes the connection instead of returning it to the pool.

    @param options

    timeout is how many seconds to wait for the running queries of this client. The default is 0.

  • name: string
    ): Promise<void>;

    Commits a distributed transaction, also known as a prepared transaction in PostgreSQL or an XA transaction in MySQL

    @param name

    Name of the distributed transaction

    await sql.commitDistributed("my_distributed_transaction");
  • connect(): Promise<SQL>;

    Waits for the database connection to be established. Opens one connection if the pool has none.

    await sql.connect();
  • name: string,
    ): Promise<ContextCallbackResult<T>>;

    Begins a distributed transaction. Alias of beginDistributed.

  • options?: { timeout: number }
    ): Promise<void>;

    Closes the database connection. Alias of SQL.close.

    @param options

    Optional timeout in seconds

    await sql.end({ timeout: 1 });
  • file<T = any>(
    filename: string,
    values?: any[] | Record<string, any>
    ): Query<T>;

    Reads a file and runs its contents as a query. The query is lazy: Bun reads the file when the query starts. Pass values as an array if the file uses positional parameters ($1 on PostgreSQL, ? on MySQL). With the SQLite adapter, values may also be an object of named parameters (:name, $name, or @name placeholders). A key works with or without the prefix.

    const result = await sql.file("query.sql", [1, 2, 3]);
  • flush(): void;

    Flushes any pending operations. Does nothing on SQLite, where queries run synchronously.

    sql.flush();
  • value: unknown
    ): undefined | string | SQLJSONParameter;

    Returns a parameter that stores value as JSON, to interpolate into a query. It works on every adapter.

    Bun sends an object or an array as JSON by itself, and PostgreSQL stores a string in a json or jsonb column as a JSON string. Use sql.json to store a JSON number, boolean or null, to store an object or an array on SQLite, and to store a JSON string where Bun sends a string as it is: MySQL, MariaDB, SQLite, and PostgreSQL with prepare: false.

    await sql`INSERT INTO settings (data) VALUES (${sql.json(42)})`; // 42
    await sql`INSERT INTO settings (data) VALUES (${sql.json(null)})`; // JSON null, not SQL NULL
    await sql`INSERT INTO settings (data) VALUES (${sql.json("dark")})`; // "dark"
  • channel: string,
    onnotify: (payload: string) => void,
    onlisten?: () => void
    ): Promise<ListenSubscription>;

    Subscribe to a PostgreSQL LISTEN channel. Resolves once the server has acknowledged the subscription, with a handle that removes it again.

    Every call is its own registration: several on one channel share a single server-side subscription and each receives every notification. All of them share one dedicated connection, opened by the first listen() and closed when the last registration is removed. If it drops, it is reconnected with exponential backoff and every channel is re-subscribed; onlisten runs again each time.

    A throwing onnotify or onlisten is reported as an uncaught exception.

    @param channel

    Channel name, quoted for you; at most 63 bytes, the PostgreSQL identifier limit

    @param onnotify

    Receives each notification's payload

    @param onlisten

    Runs once the LISTEN is acknowledged, initially and after every reconnect

    const subscription = await sql.listen("events", payload => console.log(payload));
    await sql.notify("events", "hello");
    await subscription.unlisten();
  • channel: string,
    payload?: string
    ): Promise<void>;

    Send a PostgreSQL NOTIFY via pg_notify. Runs as a normal query on this handle, so on a sql.begin() transaction it is delivered on commit and discarded on rollback. Omitting payload sends an empty one, like a bare NOTIFY channel.

    await sql.notify("events", JSON.stringify({ id: 1 }));
    await sql.notify("cache-invalidated");
  • release(): Promise<void>;

    Releases the connection back to the pool.

    The client closes immediately: new queries and begin() calls reject. A transaction started with begin() on this client keeps the connection until it ends, and the pool gets the connection back after that. The returned promise resolves right away, so you can await release() inside such a transaction.

    Bun closes a connection that is released inside an open transaction, for example after a manual BEGIN, instead of returning it to the pool.

  • options?: { signal: AbortSignal }
    ): Promise<ReservedSQL>;

    Reserves a connection from the pool and returns a client that wraps that single connection. Use it to run queries on an isolated connection.

    Calling reserve() on a reserved client returns a new reserved connection, not the same one (behavior matches the postgres package).

    @param options

    signal aborts the reservation while it is still waiting for a connection; the returned promise rejects with signal.reason and no connection is taken from the pool. Aborting after the promise resolved has no effect: the caller owns the connection and must release() it.

    Rejects if the adapter does not support connection pooling (SQLite).

    const reserved = await sql.reserve();
    await reserved`select * from users`;
    await reserved.release();
    
    // In production, release in a finally block
    const reserved = await sql.reserve();
    try {
      // ... queries
    } finally {
      await reserved.release();
    }
    
    // Bun supports Symbol.dispose and Symbol.asyncDispose,
    // so `using` releases the connection at the end of the scope
    using reserved = await sql.reserve()
    await reserved`select * from users`
    
    // Give up on the reservation if no connection frees up in time
    const reserved = await sql.reserve({ signal: AbortSignal.timeout(5000) });
  • name: string
    ): Promise<void>;

    Rolls back a distributed transaction, also known as a prepared transaction in PostgreSQL or an XA transaction in MySQL

    @param name

    Name of the distributed transaction

    await sql.rollbackDistributed("my_distributed_transaction");
  • ): Promise<ContextCallbackResult<T>>;

    Begins a new transaction. Alias of begin.

    Reserves a connection for the transaction and passes a scoped sql instance to the callback. sql.transaction resolves with the callback's return value. BEGIN is sent automatically, and if anything fails, ROLLBACK is sent so the connection can be released and execution can continue.

    const [user, account] = await sql.transaction(async sql => {
      const [user] = await sql`
        insert into users (
          name
        ) values (
          'Murray'
        )
        returning *
      `
      const [account] = await sql`
        insert into accounts (
          user_id
        ) values (
          ${ user.user_id }
        )
        returning *
      `
      return [user, account]
    })
    options: string,
    ): Promise<ContextCallbackResult<T>>;

    Begins a new transaction with options. Alias of begin.

    Reserves a connection for the transaction and passes a scoped sql instance to the callback. sql.transaction resolves with the callback's return value. BEGIN is sent with the given options, and if anything fails, ROLLBACK is sent so the connection can be released and execution can continue.

    const [user, account] = await sql.transaction("read write", async sql => {
      const [user] = await sql`
        insert into users (
          name
        ) values (
          'Murray'
        )
        returning *
      `
      const [account] = await sql`
        insert into accounts (
          user_id
        ) values (
          ${ user.user_id }
        )
        returning *
      `
      return [user, account]
    });
  • unsafe<T = any>(
    string: string,
    values?: any[] | Record<string, any>
    ): Query<T>;

    Executes any query string as-is. This can lead to SQL injection if the string contains untrusted input.

    The string takes the database's own placeholders: $1 on PostgreSQL, ? on MySQL, either on SQLite. Pass values as an array, which Bun copies in the call. Without values, the string can hold several statements.

    sql.unsafe can be nested inside a safe sql expression, for example when only part of the query is unsafe. Bun adds the nested text as written. On PostgreSQL, a nested sql.unsafe that has values cannot follow other parameters, because $1 in its text is the first parameter of the whole query: such a query rejects with a SyntaxError.

    With the SQLite adapter, values may also be an object of named parameters (:name, $name, or @name placeholders). A key works with or without the prefix. This form does not work in a nested sql.unsafe.

    const result = await sql.unsafe(`select ${danger} from users where id = ${dragons}`)
    const row = await sql.unsafe("select * from users where id = :id", { id: 1 })

Referenced types

interface Query<T>

A pending SQL query. Extends Promise, so it can be awaited, and adds methods to control how it runs. The array it resolves to also has ResultMetadata.

A query is lazy. It starts in the call to then(), catch(), finally() or execute, and await calls then().

What then() and catch() return is a promise like any other: when it rejects with nothing to handle the rejection, that is reported as an unhandled rejection. So is an error that a finally() callback throws.

The failure of a query that was only started, with execute() or finally(), is not reported once it has a connection, nor when close({ timeout: 0 }) closes the pool while it waits for one, when it was cancelled before it started, or when its reservation, transaction or savepoint has ended. After execute(), a failure to connect, a pool that was already closed, a cancel() or the end of the time of close({ timeout }), with a timeout above 0, while it waits for a connection, and a query that cannot be built are reported. So is the failure of a query that SQLite runs outside a transaction.

Bun reads the parameters when it sends the query. Leave a Buffer, TypedArray, Date or object that you passed alone until the query settles.

  • readonly [Symbol.toStringTag]: string
  • active: boolean

    True while a connection runs the query

  • cancelled: boolean

    True after cancel was called

  • cancel(): Query<T>;

    Cancels the query.

    A query that Bun has not sent yet never runs. It rejects with ERR_POSTGRES_QUERY_CANCELLED (or the MYSQL / SQLITE code).

    PostgreSQL: Bun asks the server to stop a running query, on a second connection. The query rejects with the server's error, errno "57014", or resolves if it ends first. A query that Bun sent behind another one, or that has another one sent behind it, rejects with ERR_POSTGRES_QUERY_CANCELLED and a hint, because the server may still run it.

    MySQL: a query that Bun has sent runs to the end and settles with its result.

  • catch<TResult = never>(
    onrejected?: null | (reason: any) => TResult | PromiseLike<TResult>
    ): Promise<T & ResultMetadata | TResult>;

    Attaches a callback for only the rejection of the Promise.

    @param onrejected

    The callback to execute when the Promise is rejected.

    @returns

    A Promise for the completion of the callback.

  • execute(): Query<T>;

    Starts executing the query. Queries are lazy: they only run when awaited or executed with this method.

  • onfinally?: null | () => void
    ): Promise<T & ResultMetadata>;

    Attaches a callback that is invoked when the Promise is settled (fulfilled or rejected). The resolved value cannot be modified from the callback.

    @param onfinally

    The callback to execute when the Promise is settled (fulfilled or rejected).

    @returns

    A Promise for the completion of the callback.

  • raw(): Query<T>;

    Returns rows as arrays of Buffer objects instead of objects.

    PostgreSQL and MySQL: the bytes the server sent. On PostgreSQL a prepared query gets bool, int4, float4, float8, numeric, bytea, time, timestamp, timestamptz, int4[] and float4[] in binary and every other type as text; all types are text on the first run of a query without parameters, with .simple() and with prepare: false. On MySQL a prepared query is binary. SQLite: Uint8Array objects.

    Call it before the query starts. After that, SQLite ignores it, and on PostgreSQL some types can arrive in the other format.

  • PostgreSQL only. Starts a COPY ... TO STDOUT query and returns the bytes that the server sends, in the format that the statement names. A chunk can end in the middle of a row.

    Call it before the query starts. The query takes no parameters, and resolves with the row count in count when the server has finished. A failure reaches the stream, so the query needs no handler of its own.

    await Bun.write("users.csv", new Response(sql`COPY users TO STDOUT (FORMAT csv)`.readable()));
  • simple(): Query<T>;

    Executes the query as a simple query. Parameters are not allowed, but the query can contain multiple commands separated by semicolons.

  • then<TResult1 = T & ResultMetadata, TResult2 = never>(
    onfulfilled?: null | (value: T & ResultMetadata) => TResult1 | PromiseLike<TResult1>,
    onrejected?: null | (reason: any) => TResult2 | PromiseLike<TResult2>
    ): Promise<TResult1 | TResult2>;

    Attaches callbacks for the resolution and/or rejection of the Promise.

    @param onfulfilled

    The callback to execute when the Promise is resolved.

    @param onrejected

    The callback to execute when the Promise is rejected.

    @returns

    A Promise for the completion of which ever callback is executed.

  • values(): Query<T>;

    Returns each row as an array of values, in the same order as the columns in the query.

    It has no effect after execute() on SQLite, which has run the query.

  • writable(): WritableStream<string | ArrayBufferLike | TypedArray<ArrayBufferLike> | DataView<ArrayBufferLike>>;

    PostgreSQL only. Starts a COPY ... FROM STDIN query and returns a stream that takes the bytes for the server, in the format that the statement names.

    close() resolves when the server has stored the rows, and rejects with the server's error. abort() stores nothing. The connection runs nothing else until then, so always close or abort the stream. Bun aborts a stream that is still open when its transaction, savepoint or reservation ends.

    Call it before the query starts. The query takes no parameters, and resolves with the row count in count.

    await Bun.file("users.csv").stream().pipeTo(sql`COPY users FROM STDIN (FORMAT csv)`.writable());

interface Helper<T>

A parameter or serializable value interpolated into a query.

const helper = sql(users, 'id');
await sql`insert into users ${helper}`;