### Pre-run Setup for Benchmarks

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/demo/benchmarks/index.html

Executes a PRAGMA command to set the journal mode before running benchmarks. This is a common setup step for database performance testing.

```sql
-- Pre-run setup
PRAGMA journal_mode=delete;
Start
```

--------------------------------

### Benchmark Setup: Journal Mode

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/demo/benchmarks/benchmarks.html

Sets the journal mode to delete for benchmark preparation. This is a common setup step for database benchmarks.

```sql
-- Pre-run setup PRAGMA journal_mode=delete;
Start
```

--------------------------------

### SQL Initialization and Query

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/demo/hello/hello.html

Example SQL statements to create a table, insert data, and select from it.

```sql
CREATE TABLE IF NOT EXISTS t(x PRIMARY KEY); INSERT OR REPLACE INTO t VALUES ('foo'), ('bar'); SELECT * FROM t;
```

--------------------------------

### Load wa-sqlite Library and Execute SQL

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/README.md

Demonstrates loading the wa-sqlite library asynchronously and executing a simple SQL query. This example uses ES6 modules and requires a factory function to initialize the SQLite instance.

```javascript
import SQLiteESMFactory from '@journeyapps/wa-sqlite/dist/wa-sqlite.mjs';
import * as SQLite from '@journeyapps/wa-sqlite';

async function hello() {
  const module = await SQLiteESMFactory();
  const sqlite3 = SQLite.Factory(module);
  const db = await sqlite3.open_v2('myDB');
  await sqlite3.exec(db, `SELECT 'Hello, world!'`, (row, columns) => {
    console.log(row);
  });
  await sqlite3.close(db);
}

hello();
```

--------------------------------

### Creating a SQLiteAPI Instance

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Follow these steps to create an instance of the SQLite API. This example demonstrates importing the necessary modules, invoking the ES6 module factory to create the SQLite Emscripten module, and then using the module to build the API instance. Finally, it shows how to use the API to open a database.

```javascript
// Import an ES6 module factory function from one of the
// package builds, either 'wa-sqlite.mjs' (synchronous) or
// 'wa-sqlite-async.mjs' (asynchronous). You should only
// use the asynchronous build if you plan to use an
// asynchronous VFS or module.import SQLiteESMFactory from 'wa-sqlite/dist/wa-sqlite.mjs';

// Import the Javascript API wrappers.
import * as SQLite from 'wa-sqlite';

// Use an async function to simplify Promise handling.
(async function() {
  // Invoke the ES6 module factory to create the SQLite
  // Emscripten module. This will fetch and compile the
  // .wasm file.
  const module = await SQLiteESMFactory();

  // Use the module to build the API instance.
  const sqlite3 = SQLite.Factory(module);

  // Use the API to open and access a database.
  const db = await sqlite3.open_v2('myDB');

  // ...
})();
```

--------------------------------

### Web Worker and MessageChannel Setup

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/demo/hello/index.html

Loads the wa-sqlite script, either in the main window or a web worker, using MessageChannel for communication.

```javascript
// Load script in the Window or in a Worker, depending on whether
// the URL contains a "worker" query parameter. Use a MessageChannel
// to communicate with the script.
const { port1, port2 } = new MessageChannel();
const searchParams = new URLSearchParams(window.location.search);
if (searchParams.has('worker')) {
  document.querySelector('h1').textContent = 'Running in a Worker';
  const worker = new Worker('./hello.js', { type: 'module' });
  worker.postMessage('messagePort', [port2])
} else {
  document.querySelector('h1').textContent = 'Running in the Window';
  await import('./hello.js')
  window.postMessage('messagePort', '*', [port2]);
}
// Submit SQL over the MessageChannel.
document.getElementById('submit').addEventListener('click', () => {
  port1.postMessage(document.getElementById('input').value);
});
// Handle query results.
port1.addEventListener('message', (event) => {
  console.log(event.data);
  const output = document.getElementById('output');
  output.innerHTML = '';
  if (Array.isArray(event.data)) {
    for (const { columns, rows } of event.data) {
      output.appendChild(buildHTMLTable(columns, rows));
    }
  } else {
    output.textContent = 'Error: ' + event.data.error;
  }
});
port1.start();
function buildHTMLTable(columns, rows) {
  function tx(tag, data) {
    const tx = document.createElement(tag);
    tx.textContent = data.toString();
    return tx;
  }
  const table = document.createElement('table');
  const thead = document.createElement('thead');
  const tr = document.createElement('tr');
  columns.forEach(column => tr.appendChild(tx('th', column)));
  thead.appendChild(tr);
  table.appendChild(thead);
  const tbody = document.createElement('tbody');
  rows.forEach(row => {
    const tr = document.createElement('tr');
    row.forEach(cell => tr.appendChild(tx('td', cell)));
    tbody.appendChild(tr);
  });
  table.appendChild(tbody);
  return table;
}
```

--------------------------------

### xFileSize

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteVFS.html

Gets the current size of a file.

```APIDOC
## xFileSize

### Description
Gets the current size of a file.

### Method
(Not specified, likely internal VFS operation)

### Parameters
#### Path Parameters
* **pFile** (number) - Description not specified.
* **pSize** (number) - Description not specified.

### Returns
* number | Promise<number> - The size of the file.

### See
[https://sqlite.org/c3ref/io_methods.html](https://sqlite.org/c3ref/io_methods.html)
```

--------------------------------

### bind_int64

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds a 64-bit integer number to a prepared statement parameter. Binding indices start from 1.

```APIDOC
## bind_int64

### Description
Binds a 64-bit integer number (bigint) to a prepared statement parameter.

### Method
(Implicitly called within a JavaScript context, not a direct HTTP method)

### Parameters
#### Parameters
*   **stmt**: number - prepared statement pointer
*   **i**: number - binding index (starts from 1)
*   **value**: bigint - The 64-bit integer to bind

### Returns
number - `SQLITE_OK` (throws exception on error)

### See
[https://www.sqlite.org/c3ref/bind_blob.html](https://www.sqlite.org/c3ref/bind_blob.html)
```

--------------------------------

### Get Number of Bound Parameters

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Retrieves the total number of binding locations in a prepared statement.

```typescript
sqlite3.bind_parameter_count(stmt);
```

--------------------------------

### bind_blob

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds a blob value to a prepared statement parameter. Binding indices start from 1.

```APIDOC
## bind_blob

### Description
Binds a blob value to a prepared statement parameter. Binding indices start from 1.

### Method
(Not specified, likely a function call in an SDK)

### Parameters
#### Path Parameters
(None)

#### Query Parameters
(None)

#### Request Body
(Not applicable)

### Parameters
*   **stmt** (number) - prepared statement pointer
*   **i** (number) - binding index
*   **value** (number[] | Uint8Array) - The blob value to bind

### Returns
*   **number** - `SQLITE_OK` (throws exception on error)

### See
*   [https://www.sqlite.org/c3ref/bind_blob.html](https://www.sqlite.org/c3ref/bind_blob.html)
```

--------------------------------

### bind_int

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds an integer number to a prepared statement parameter. Binding indices start from 1.

```APIDOC
## bind_int

### Description
Binds an integer number to a prepared statement parameter.

### Method
(Implicitly called within a JavaScript context, not a direct HTTP method)

### Parameters
#### Parameters
*   **stmt**: number - prepared statement pointer
*   **i**: number - binding index (starts from 1)
*   **value**: number - The integer to bind

### Returns
number - `SQLITE_OK` (throws exception on error)

### See
[https://www.sqlite.org/c3ref/bind_blob.html](https://www.sqlite.org/c3ref/bind_blob.html)
```

--------------------------------

### Bind Collection of Values to Statement

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds values from an array or object to a prepared statement. Array values are bound implicitly by index, while object values are bound by named parameters (prefixed with ':', '@', or '$'). Note that SQLite indices start at 1, while array indices start at 0.

```typescript
const sql = 'INSERT INTO tbl VALUES (?, ?, ?)';
for await (const stmt of sqlite3.statements(db, sql)) {
  sqlite3.bind_collection(stmt, [42, 'hello', null]);
  ...
```

```typescript
const sql = 'INSERT INTO tbl VALUES (?, ?, ?)';
for await (const stmt of sqlite3.statements(db, sql)) {
  sqlite3.bind_collection(stmt, {
    '@foo': 42,
    '@bar': 'hello',
    '@baz': null,
  });
  ...
```

--------------------------------

### bind_null

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds a NULL value to a prepared statement parameter. Binding indices start from 1.

```APIDOC
## bind_null

### Description
Binds a NULL value to a prepared statement parameter.

### Method
(Implicitly called within a JavaScript context, not a direct HTTP method)

### Parameters
#### Parameters
*   **stmt**: number - prepared statement pointer
*   **i**: number - binding index (starts from 1)

### Returns
number - `SQLITE_OK` (throws exception on error)

### See
[https://www.sqlite.org/c3ref/bind_blob.html](https://www.sqlite.org/c3ref/bind_blob.html)
```

--------------------------------

### bind

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds a value to a prepared statement parameter. This function automatically selects the appropriate bind_* function based on the value's type. Binding indices start from 1.

```APIDOC
## bind

### Description
Binds a value to a prepared statement parameter. This function automatically selects the appropriate bind_* function based on the value's type. Binding indices start from 1.

### Method
(Not specified, likely a function call in an SDK)

### Parameters
#### Path Parameters
(None)

#### Query Parameters
(None)

#### Request Body
(Not applicable)

### Parameters
*   **stmt** (number) - prepared statement pointer
*   **i** (number) - binding index
*   **value** ([SQLiteCompatibleType]) - The value to bind

### Returns
*   **number** - `SQLITE_OK` (throws exception on error)
```

--------------------------------

### bind_text

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds a string value to a specified parameter in a prepared SQL statement. Parameter indices start from 1.

```APIDOC
## bind_text(stmt, i, value)

### Description
Binds a string value to a prepared statement.

Note that binding indices begin with 1.

### Parameters
#### Path Parameters
*   **stmt** (number) - Required - prepared statement pointer
*   **i** (number) - Required - binding index
*   **value** (string) - Required - The string value to bind

### Returns
`SQLITE_OK` (throws exception on error)
```

--------------------------------

### bind_double

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds a double-precision floating-point number to a prepared statement parameter. Binding indices start from 1.

```APIDOC
## bind_double

### Description
Binds a number (double-precision float) to a prepared statement parameter.

### Method
(Implicitly called within a JavaScript context, not a direct HTTP method)

### Parameters
#### Parameters
*   **stmt**: number - prepared statement pointer
*   **i**: number - binding index (starts from 1)
*   **value**: number - The number to bind

### Returns
number - `SQLITE_OK` (throws exception on error)

### See
[https://www.sqlite.org/c3ref/bind_blob.html](https://www.sqlite.org/c3ref/bind_blob.html)
```

--------------------------------

### Bind Integer to Prepared Statement Parameter

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds an integer value to a specific parameter index in a prepared statement. Binding indices start at 1.

```typescript
sqlite3.bind_int(stmt, i, value);
```

--------------------------------

### Bind BigInt to Prepared Statement Parameter

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds a BigInt value to a specific parameter index in a prepared statement. Binding indices start at 1.

```typescript
sqlite3.bind_int64(stmt, i, value);
```

--------------------------------

### Bind Double to Prepared Statement Parameter

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds a number value to a specific parameter index in a prepared statement. Binding indices start at 1.

```typescript
sqlite3.bind_double(stmt, i, value);
```

--------------------------------

### Get Name of Bound Parameter

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Retrieves the name of a bound parameter at a specific index. Binding indices start at 1.

```typescript
sqlite3.bind_parameter_name(stmt, i);
```

--------------------------------

### value_type

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Gets the type of an sqlite3_value pointer.

```APIDOC
## value_type(pValue)

### Description
Get type of `sqlite3_value`.

### Parameters
#### Path Parameters
* **pValue** (number) - Required - `sqlite3_value` pointer

### Returns number
enumeration value for type

### See
[https://sqlite.org/c3ref/value_blob.html](https://sqlite.org/c3ref/value_blob.html)
```

--------------------------------

### open_v2(zFilename, iFlags?, zVfs?)

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Opens a new database connection. Returns a Promise-wrapped database pointer.

```APIDOC
## open_v2(zFilename, iFlags?, zVfs?)

### Description
Opening a new database connection.
Note that this function differs from the C API in that it returns the Promise-wrapped database pointer (instead of a result code).

### Parameters
#### Path Parameters
* **zFilename** (string) - Required
* **iFlags** (number) - Optional - `SQLite.SQLITE_OPEN_CREATE | SQLite.SQLITE_OPEN_READWRITE` (0x6) if omitted
* **zVfs** (string) - Optional - VFS name

### Returns
Promise<number> - Promise-wrapped database pointer.

### See
[https://sqlite.org/c3ref/open.html](https://sqlite.org/c3ref/open.html)
```

--------------------------------

### SQLiteAPI Instance Creation and Usage

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

This snippet demonstrates how to import the wa-sqlite ES6 module factory, create an instance of the SQLite API, and open a database. It highlights the use of an async function to handle Promises returned by certain API operations.

```APIDOC
## SQLiteAPI Instance Creation and Usage

### Description
This section details the process of initializing and using the wa-sqlite API. It covers importing the necessary modules, creating an API instance, and opening a database connection. Note that some operations, like opening/closing databases or executing statements, may return Promises to support both synchronous and asynchronous SQLite builds.

### Usage

1.  **Import Factory Function**: Import an ES6 module factory function from either `wa-sqlite.mjs` (synchronous) or `wa-sqlite-async.mjs` (asynchronous).
2.  **Import API Wrappers**: Import the JavaScript API wrappers.
3.  **Create API Instance**: Use an async function to invoke the factory and create the SQLite Emscripten module, then use this module to build the API instance.
4.  **Open Database**: Use the API instance to open a database.

### Code Example

```javascript
// Import an ES6 module factory function from one of the
// package builds, either 'wa-sqlite.mjs' (synchronous) or
// 'wa-sqlite-async.mjs' (asynchronous). You should only
// use the asynchronous build if you plan to use an
// asynchronous VFS or module.
import SQLiteESMFactory from 'wa-sqlite/dist/wa-sqlite.mjs';

// Import the Javascript API wrappers.
import * as SQLite from 'wa-sqlite';

// Use an async function to simplify Promise handling.
(async function() {
  // Invoke the ES6 module factory to create the SQLite
  // Emscripten module. This will fetch and compile the
  // .wasm file.
  const module = await SQLiteESMFactory();

  // Use the module to build the API instance.
  const sqlite3 = SQLite.Factory(module);

  // Use the API to open and access a database.
  const db = await sqlite3.open_v2('myDB');

  // ... further database operations ...
})();
```

### Notes
- For C functions that return an error code, the corresponding JavaScript wrapper will throw an exception with a `code` property on error.
- Functions involved in opening/closing a database or executing a statement may return a `Promise`.
```

--------------------------------

### Build wa-sqlite with Make

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/README.md

Build the wa-sqlite project using the Makefile. The -B flag forces a rebuild.

```bash
make -B
```

--------------------------------

### bind_parameter_name

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Retrieves the name of a bound parameter at a specific index. Binding indices start from 1.

```APIDOC
## bind_parameter_name

### Description
Gets the name of a bound parameter at a specific index.

### Method
(Implicitly called within a JavaScript context, not a direct HTTP method)

### Parameters
#### Parameters
*   **stmt**: number - prepared statement pointer
*   **i**: number - binding index (starts from 1)

### Returns
string - The binding name.

### See
[https://www.sqlite.org/c3ref/bind_parameter_name.html](https://www.sqlite.org/c3ref/bind_parameter_name.html)
```

--------------------------------

### SQL Preamble for Write Hint Test

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/demo/write-hint/index.html

This SQL statement sets up the initial table structure for the write hint test.

```sql
CREATE TABLE t(x);
```

--------------------------------

### xSync

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteVFS.html

Synchronizes data to disk for a file.

```APIDOC
## xSync

### Description
Synchronizes data to disk for a file.

### Method
(Not specified, likely internal VFS operation)

### Parameters
#### Path Parameters
* **pFile** (number) - Description not specified.
* **flags** (number) - Description not specified.

### Returns
* number | Promise<number> - The result of the sync operation.

### See
[https://sqlite.org/c3ref/io_methods.html](https://sqlite.org/c3ref/io_methods.html)
```

--------------------------------

### xOpen

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteVFS.html

Opens a file within the virtual file system.

```APIDOC
## xOpen

### Description
Opens a file within the virtual file system.

### Method
(Not specified, likely internal VFS operation)

### Parameters
#### Path Parameters
* **pVfs** (number) - Description not specified.
* **zName** (number) - Description not specified.
* **pFile** (number) - Description not specified.
* **flags** (number) - Description not specified.
* **pOutFlags** (number) - Description not specified.

### Returns
* number | Promise<number> - The result of the open operation.

### See
[https://sqlite.org/c3ref/vfs.html](https://sqlite.org/c3ref/vfs.html)
```

--------------------------------

### SQLiteVFS Interface Methods

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteVFS.html

This section details the methods available in the SQLiteVFS interface. Each method can be implemented synchronously or asynchronously.

```APIDOC
## Interface SQLiteVFS

SQLite Virtual File System object

Objects with this interface can be passed to [SQLiteAPI.vfs_register](SQLiteAPI.html#vfs_register) to define a new filesystem.

### Methods

#### xAccess

*   **Description**: Checks if a file has certain access permissions.
*   **Parameters**:
    *   `pVfs` (number)
    *   `zName` (number)
    *   `flags` (number)
    *   `pResOut` (number)
*   **Returns**: `number | Promise<number>`
*   **See**: [https://sqlite.org/c3ref/vfs.html](https://sqlite.org/c3ref/vfs.html)

#### xCheckReservedLock

*   **Description**: Checks for a reserved lock on a file.
*   **Parameters**:
    *   `pFile` (number)
    *   `pResOut` (number)
*   **Returns**: `number | Promise<number>`
*   **See**: [https://sqlite.org/c3ref/io_methods.html](https://sqlite.org/c3ref/io_methods.html)

#### xClose

*   **Description**: Closes a file.
*   **Parameters**:
    *   `pFile` (number)
*   **Returns**: `number | Promise<number>`
*   **See**: [https://sqlite.org/c3ref/io_methods.html](https://sqlite.org/c3ref/io_methods.html)

#### xDelete

*   **Description**: Deletes a file.
*   **Parameters**:
    *   `pVfs` (number)
    *   `zName` (number)
    *   `syncDir` (number)
*   **Returns**: `number | Promise<number>`

#### xDeviceCharacteristics

*   **Description**: Returns the device characteristics of a file.
*   **Parameters**:
    *   `pFile` (number)
*   **Returns**: `number | Promise<number>`

#### xFileControl

*   **Description**: Performs a file control operation.
*   **Parameters**:
    *   `pFile` (number)
    *   `op` (number)
    *   `pArg` (number)
*   **Returns**: `number | Promise<number>`

#### xFileSize

*   **Description**: Gets the size of a file.
*   **Parameters**:
    *   `pFile` (number)
    *   `pSize` (number)
*   **Returns**: `number | Promise<number>`

#### xFullPathname

*   **Description**: Gets the full path name of a file.
*   **Parameters**:
    *   `pVfs` (number)
    *   `zName` (number)
    *   `nOut` (number)
    *   `zOut` (number)
*   **Returns**: `number | Promise<number>`

#### xGetLastError

*   **Description**: Gets the last error message.
*   **Parameters**:
    *   `pVfs` (number)
    *   `nBuf` (number)
    *   `zBuf` (number)
*   **Returns**: `number | Promise<number>`

#### xLock

*   **Description**: Acquires a lock on a file.
*   **Parameters**:
    *   `pFile` (number)
    *   `lockType` (number)
*   **Returns**: `number | Promise<number>`

#### xOpen

*   **Description**: Opens a file.
*   **Parameters**:
    *   `pVfs` (number)
    *   `zName` (number)
    *   `pFile` (number)
    *   `flags` (number)
    *   `pOutFlags` (number)
*   **Returns**: `number | Promise<number>`

#### xRead

*   **Description**: Reads data from a file.
*   **Parameters**:
    *   `pFile` (number)
    *   `pData` (number)
    *   `iAmt` (number)
    *   `iOffsetLo` (number)
    *   `iOffsetHi` (number)
*   **Returns**: `number | Promise<number>`

#### xSectorSize

*   **Description**: Gets the sector size of a file.
*   **Parameters**:
    *   `pFile` (number)
*   **Returns**: `number | Promise<number>`

#### xSync

*   **Description**: Synchronizes file changes.
*   **Parameters**:
    *   `pFile` (number)
    *   `flags` (number)
*   **Returns**: `number | Promise<number>`

#### xTruncate

*   **Description**: Truncates a file to a specified size.
*   **Parameters**:
    *   `pFile` (number)
    *   `sizeLo` (number)
    *   `sizeHi` (number)
*   **Returns**: `number | Promise<number>`

#### xUnlock

*   **Description**: Releases a lock on a file.
*   **Parameters**:
    *   `pFile` (number)
    *   `lockType` (number)
*   **Returns**: `number | Promise<number>`

#### xWrite

*   **Description**: Writes data to a file.
*   **Parameters**:
    *   `pFile` (number)
    *   `pData` (number)
    *   `iAmt` (number)
    *   `iOffsetLo` (number)
    *   `iOffsetHi` (number)
*   **Returns**: `number | Promise<number>`
```

--------------------------------

### libversion()

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Retrieves the version of the SQLite library as a string array.

```APIDOC
## libversion()

### Description
Get SQLite library version.

### Returns
string - version string, e.g. '3.35.5'

### See
[https://www.sqlite.org/c3ref/libversion.html](https://www.sqlite.org/c3ref/libversion.html)
```

--------------------------------

### SQLitePrepareOptions Interface

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLitePrepareOptions.html

Defines options for preparing SQL statements. It can include flags to modify preparation behavior and an unscoped option to control statement lifetime.

```APIDOC
## Interface SQLitePrepareOptions

Options object argument for [SQLiteAPI.statements](SQLiteAPI.html#statements)

### Properties

*   **flags?** (number) - Optional - SQLITE_PREPARE_* flags. See [https://sqlite.org/c3ref/c_prepare_dont_log.html#sqlitepreparepersistent](https://sqlite.org/c3ref/c_prepare_dont_log.html#sqlitepreparepersistent)
*   **unscoped?** (boolean) - Optional - Set to `true` to give iterated statements an arbitrary lifetime, otherwise they are valid only within the scope of an iteration.
```

--------------------------------

### Clone wa-sqlite Repository

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/README.md

Clone the wa-sqlite repository to your local machine.

```bash
git clone [this repo]
```

--------------------------------

### Bind Null to Prepared Statement

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Binds a null value to a specific parameter index in a prepared statement. Binding indices start at 1.

```typescript
sqlite3.bind_null(stmt, i);
```

--------------------------------

### SQL Transaction with Write Hint

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/demo/write-hint/index.html

This SQL transaction simulates a write hint using PRAGMA and inserts data into a table, returning the inserted value if a condition is met. It's designed for deadlock-free synchronization.

```sql
PRAGMA write_hint; -- simulate fcntl write transaction hint
WITH cnt AS (
  SELECT COUNT() AS n FROM t
)
INSERT INTO t
SELECT * FROM cnt WHERE n < 500
RETURNING *;
```

--------------------------------

### JavaScript for Web Worker or Window Execution

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/demo/hello/hello.html

Loads the wa-sqlite script either in the main window or a web worker based on URL parameters. Uses MessageChannel for communication.

```javascript
// Load script in the Window or in a Worker, depending on whether
// the URL contains a "worker" query parameter. Use a MessageChannel
// to communicate with the script.
const { port1, port2 } = new MessageChannel();
const searchParams = new URLSearchParams(window.location.search);
if (searchParams.has('worker')) {
    document.querySelector('h1').textContent = 'Running in a Worker';
    const worker = new Worker('./hello.js', { type: 'module' });
    worker.postMessage('messagePort', [port2])
} else {
    document.querySelector('h1').textContent = 'Running in the Window';
    await import('./hello.js')
    window.postMessage('messagePort', '*', [port2]);
}

// Submit SQL over the MessageChannel.
document.getElementById('submit').addEventListener('click', () => {
    port1.postMessage(document.getElementById('input').value);
});

// Handle query results.
port1.addEventListener('message', (event) => {
    console.log(event.data);
    const output = document.getElementById('output');
    output.innerHTML = '';
    if (Array.isArray(event.data)) {
        for (const { columns, rows } of event.data) {
            output.appendChild(buildHTMLTable(columns, rows));
        }
    } else {
        output.textContent = 'Error: ' + event.data.error;
    }
});
port1.start();

function buildHTMLTable(columns, rows) {
    function tx(tag, data) {
        const tx = document.createElement(tag);
        tx.textContent = data.toString();
        return tx;
    }
    const table = document.createElement('table');
    const thead = document.createElement('thead');
    const tr = document.createElement('tr');
    columns.forEach(column => tr.appendChild(tx('th', column)));
    thead.appendChild(tr);
    table.appendChild(thead);
    const tbody = document.createElement('tbody');
    rows.forEach(row => {
        const tr = document.createElement('tr');
        row.forEach(cell => tr.appendChild(tx('td', cell)));
        tbody.appendChild(tr);
    });
    table.appendChild(tbody);
    return table;
}
```

--------------------------------

### vfs_register

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Registers a new Virtual File System (VFS) with SQLite. Optionally sets it as the default VFS.

```APIDOC
## vfs_register(vfs, makeDefault)

### Description
Register a new Virtual File System.

### Parameters
#### Path Parameters
* **vfs** ([SQLiteVFS](SQLiteVFS.html)) - Required - VFS object
* **makeDefault** (boolean) - Optional

### Returns number
`SQLITE_OK` (throws exception on error)

### See
[https://www.sqlite.org/c3ref/vfs_find.html](https://www.sqlite.org/c3ref/vfs_find.html)
```

--------------------------------

### step

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Evaluates an SQL statement, returning SQLITE_ROW or SQLITE_DONE.

```APIDOC
## step(stmt)

### Description
Evaluates an SQL statement.

### Parameters
*   **stmt** (number) - Required - prepared statement pointer

### Returns
Promise<number> - Promise resolving to `SQLITE_ROW` or `SQLITE_DONE` (rejects on error)

### See
[https://www.sqlite.org/c3ref/step.html](https://www.sqlite.org/c3ref/step.html)
```

--------------------------------

### exec

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Provides a one-step interface for executing SQL queries. It handles row copying and BigInt conversion for large integers, and can optionally accept a callback for processing output rows.

```APIDOC
## exec

### Description
One-step query execution interface. The implementation of this function uses [row](SQLiteAPI.html#row), which makes a copy of blobs and returns BigInt for integers outside the safe integer bounds for Number.

### Parameters

*   **db**: number - database pointer
*   **zSQL**: string - queries
*   **callback**: ((row, columns) => void) - Optional callback called for each output row
    *   **row**: [SQLiteCompatibleType](../types/SQLiteCompatibleType.html)[]
    *   **columns**: string[]

### Returns

*   **Promise<number
>** - Promise resolving to `SQLITE_OK` (rejects on error)

### See
[https://www.sqlite.org/c3ref/exec.html](https://www.sqlite.org/c3ref/exec.html)
```

--------------------------------

### xFullPathname

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteVFS.html

Converts a file name to its full path within the VFS.

```APIDOC
## xFullPathname

### Description
Converts a file name to its full path within the VFS.

### Method
(Not specified, likely internal VFS operation)

### Parameters
#### Path Parameters
* **pVfs** (number) - Description not specified.
* **zName** (number) - Description not specified.
* **nOut** (number) - Description not specified.
* **zOut** (number) - Description not specified.

### Returns
* number | Promise<number> - The result of the full path operation.

### See
[https://sqlite.org/c3ref/vfs.html](https://sqlite.org/c3ref/vfs.html)
```

--------------------------------

### statements

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Manages statement compilation by creating an async iterator that yields a prepared statement handle on each iteration. It is typically used with a `for await` loop.

```APIDOC
## statements(db, sql, options?)

### Description
Compiles SQL statements and provides an async iterator for prepared statement handles.

### Parameters
*   **db** (number) - Required - database pointer
*   **sql** (string) - Required
*   **options** (SQLitePrepareOptions) - Optional

### Returns
AsyncIterable<number>

### See
[https://www.sqlite.org/c3ref/prepare.html](https://www.sqlite.org/c3ref/prepare.html)
```

--------------------------------

### sql

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Retrieves the SQL statement associated with a prepared statement pointer.

```APIDOC
## sql(stmt)

### Description
Get statement SQL

### Parameters
#### Path Parameters
* **stmt** (number) - Required - prepared statement pointer

### Returns string
SQL
```

--------------------------------

### xDelete

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteVFS.html

Deletes a file from the virtual file system. It takes the VFS pointer, the file name, and a sync directory flag as input.

```APIDOC
## xDelete

### Description
Deletes a file from the virtual file system.

### Method
(Not specified, likely internal VFS operation)

### Parameters
#### Path Parameters
* **pVfs** (number) - Description not specified.
* **zName** (number) - Description not specified.
* **syncDir** (number) - Description not specified.

### Returns
* number | Promise<number> - The result of the delete operation.

### See
[https://sqlite.org/c3ref/vfs.html](https://sqlite.org/c3ref/vfs.html)
```

--------------------------------

### set_authorizer

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Registers a callback function to authorize SQL statement actions. It takes a database pointer, an authorization function, and user data.

```APIDOC
## set_authorizer(db, authFunction, userData)

### Description
Register a callback function that is invoked to authorize certain SQL statement actions.

### Parameters
#### Path Parameters
* **db** (number) - Required - database pointer
* **authFunction** ((userData, iActionCode, param3, param4, param5, param6) => number | Promise<number>) - Required -
    * **Parameters**
    * **userData** (any) -
    * **iActionCode** (number) -
    * **param3** (string) -
    * **param4** (string) -
    * **param5** (string) -
    * **param6** (string) -
    #### Returns number | Promise<number>
* **userData** (any) - Required -

### Returns number
```

--------------------------------

### progress_handler(db, nProgressOps, handler, userData)

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Specifies a callback to be invoked between long-running queries.

```APIDOC
## progress_handler(db, nProgressOps, handler, userData)

### Description
Specify callback to be invoked between long-running queries
The application data passed is ignored. Use closures instead.
If any callback function returns a Promise, that function must be declared `async`, i.e. it must allow use of `await`.

### Parameters
#### Path Parameters
* **db** (number) - Required - database pointer
* **nProgressOps** (number) - Required - target number of database operations between handler invocations
* **handler** ((userData) => number | Promise<number>) - Required
    * **userData** (any) - Required
    #### Returns number | Promise<number>
* **userData** (any) - Required

### Returns
any

```

--------------------------------

### xLock

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteVFS.html

Acquires a lock on a file.

```APIDOC
## xLock

### Description
Acquires a lock on a file.

### Method
(Not specified, likely internal VFS operation)

### Parameters
#### Path Parameters
* **pFile** (number) - Description not specified.
* **lockType** (number) - Description not specified.

### Returns
* number | Promise<number> - The result of the lock operation.

### See
[https://sqlite.org/c3ref/io_methods.html](https://sqlite.org/c3ref/io_methods.html)
```

--------------------------------

### vfs_register

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Registers a new Virtual File System (VFS) with the SQLite instance. This allows for custom file system implementations.

```APIDOC
## vfs_register

### Description
Registers a new Virtual File System (VFS) with the SQLite instance. This allows for custom file system implementations.

### Method
(Not specified, likely a function call within a library)

### Parameters
#### Path Parameters
(None)

#### Query Parameters
(None)

#### Request Body
(None)

### Parameters
- **vfs**: (object) - Required - The VFS object to register.
- **makeDefault**: (boolean) - Optional - If true, this VFS will be set as the default.
```

--------------------------------

### xSectorSize

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteVFS.html

Retrieves the sector size of the device associated with a file.

```APIDOC
## xSectorSize

### Description
Retrieves the sector size of the device associated with a file.

### Method
(Not specified, likely internal VFS operation)

### Parameters
#### Path Parameters
* **pFile** (number) - Description not specified.

### Returns
* number | Promise<number> - The sector size of the device.

### See
[https://sqlite.org/c3ref/io_methods.html](https://sqlite.org/c3ref/io_methods.html)
```

--------------------------------

### column_names

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Retrieves the names of all columns for a prepared statement.

```APIDOC
## column_names(stmt)

### Description
Get names for all columns of a prepared statement.
This is a convenience function that calls [column_count](SQLiteAPI.html#column_count) and [column_name](SQLiteAPI.html#column_name).

### Parameters
#### Path Parameters
* **stmt** (number)

### Returns
string[] - array of column names
```

--------------------------------

### Execute an SQL Statement

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Evaluates a prepared SQL statement. It resolves to SQLITE_ROW for each row of data or SQLITE_DONE when execution is complete. Rejects on error.

```javascript
await sqlite3.step(stmt)
```

--------------------------------

### create_function

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Allows the creation or redefinition of SQL functions within the SQLite database. It supports asynchronous callback functions if Promises are involved.

```APIDOC
## create_function

### Description
Create or redefine SQL functions. The application data passed is ignored. Use closures instead. If any callback function returns a Promise, that function must be declared `async`.

### Parameters

*   **db**: number - database pointer
*   **zFunctionName**: string
*   **nArg**: number - number of function arguments
*   **eTextRep**: number - text encoding (and other flags)
*   **pApp**: number - application data (ignored)
*   **xFunc**: ((context, values) => void | Promise<void>) - Optional callback function
    *   **context**: number
    *   **values**: Uint32Array
*   **xStep**: ((context, values) => void | Promise<void>) - Optional callback function
    *   **context**: number
    *   **values**: Uint32Array
*   **xFinal**: ((context) => void | Promise<void>) - Optional callback function
    *   **context**: number

### Returns
*   **number** - `SQLITE_OK` (throws exception on error)

### See
[https://sqlite.org/c3ref/create_function.html](https://sqlite.org/c3ref/create_function.html)
```

--------------------------------

### libversion_number()

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Retrieves the version of the SQLite library as a number.

```APIDOC
## libversion_number()

### Description
Get SQLite library version.

### Returns
number - version number, e.g. 3035005

### See
[https://www.sqlite.org/c3ref/libversion.html](https://www.sqlite.org/c3ref/libversion.html)
```

--------------------------------

### xWrite

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteVFS.html

Writes data to a file at a specified offset. This method is part of the VFS (Virtual File System) interface for SQLite.

```APIDOC
## xWrite

### Description
Writes data to a file at a specified offset. This method is part of the VFS (Virtual File System) interface for SQLite.

### Method
(Not specified, likely internal VFS callback)

### Endpoint
(Not applicable, this is an interface method)

### Parameters
#### Path Parameters
(None)

#### Query Parameters
(None)

#### Request Body
(None)

### Parameters
* **pFile** (number) - Description of pFile parameter.
* **pData** (number) - Description of pData parameter.
* **iAmt** (number) - Description of iAmt parameter.
* **iOffsetLo** (number) - Description of iOffsetLo parameter.
* **iOffsetHi** (number) - Description of iOffsetHi parameter.

### Returns
* number | Promise<number> - The result of the write operation.
```

--------------------------------

### xFileControl

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteVFS.html

Provides a mechanism for controlling file operations through the VFS.

```APIDOC
## xFileControl

### Description
Provides a mechanism for controlling file operations through the VFS.

### Method
(Not specified, likely internal VFS operation)

### Parameters
#### Path Parameters
* **pFile** (number) - Description not specified.
* **op** (number) - Description not specified.
* **pArg** (number) - Description not specified.

### Returns
* number | Promise<number> - The result of the file control operation.

### See
[https://sqlite.org/c3ref/io_methods.html](https://sqlite.org/c3ref/io_methods.html)
```

--------------------------------

### row

Source: https://github.com/powersync-ja/wa-sqlite/blob/master/docs/interfaces/SQLiteAPI.html

Retrieves all column data for a row from a prepared statement step. It returns a copy of the blob data and BigInt for large integers.

```APIDOC
## row(stmt)

### Description
Get all column data for a row from a prepared statement step.

This convenience function will return a copy of any blob, unlike [column_blob](SQLiteAPI.html#column_blob) which returns a value referencing volatile WASM memory with short validity. Like [column](SQLiteAPI.html#column), it will return a BigInt for integers outside the safe integer bounds for Number.

### Parameters
#### Path Parameters
* **stmt** (number) - Required - prepared statement pointer

### Returns [SQLiteCompatibleType](../types/SQLiteCompatibleType.html)[ ]
row data
```