SQLite#
Added in: v22.5.0
Source Code: lib/sqlite.js
The node:sqlite module facilitates working with SQLite databases.
To access it:
import sqlite from 'node:sqlite';const sqlite = require('node:sqlite');
This module is only available under the node: scheme.
The following example shows the basic usage of the node:sqlite module to open
an in-memory database, write data to the database, and then read the data back.
import { DatabaseSync } from 'node:sqlite';
const database = new DatabaseSync(':memory:');
database.exec(`
CREATE TABLE data(
key INTEGER PRIMARY KEY,
value TEXT
) STRICT
`);
const insert = database.prepare('INSERT INTO data (key, value) VALUES (?, ?)');
insert.run(1, 'hello');
insert.run(2, 'world');
const query = database.prepare('SELECT * FROM data ORDER BY key');
console.log(query.all());
'use strict';
const { DatabaseSync } = require('node:sqlite');
const database = new DatabaseSync(':memory:');
database.exec(`
CREATE TABLE data(
key INTEGER PRIMARY KEY,
value TEXT
) STRICT
`);
const insert = database.prepare('INSERT INTO data (key, value) VALUES (?, ?)');
insert.run(1, 'hello');
insert.run(2, 'world');
const query = database.prepare('SELECT * FROM data ORDER BY key');
console.log(query.all());
Class: DatabaseSync#
This class represents a single connection to a SQLite database. All APIs
exposed by this class execute synchronously.
new DatabaseSync(path[, options])#
path <string> | <Buffer> | <URL> The path of the database. A SQLite database can be
stored in a file or completely in memory. To use a file-backed database,
the path should be a file path. To use an in-memory database, the path
should be the special name ':memory:'.
options <Object> Configuration options for the database connection. The
following options are supported:
open <boolean> If true, the database is opened by the constructor. When
this value is false, the database must be opened via the open() method.
Default: true.
readOnly <boolean> If true, the database is opened in read-only mode.
If the database does not exist, opening it will fail. Default: false.
enableForeignKeyConstraints <boolean> If true, foreign key constraints
are enabled. This is recommended but can be disabled for compatibility with
legacy database schemas. The enforcement of foreign key constraints can be
enabled and disabled after opening the database using
PRAGMA foreign_keys. Default: true.
enableDoubleQuotedStringLiterals <boolean> If true, SQLite will accept
double-quoted string literals. This is not recommended but can be
enabled for compatibility with legacy database schemas.
Default: false.
allowExtension <boolean> If true, the loadExtension SQL function
and the loadExtension() method are enabled.
You can call enableLoadExtension(false) later to disable this feature.
Default: false.
timeout <number> The busy timeout in milliseconds. This is the maximum amount of
time that SQLite will wait for a database lock to be released before
returning an error. Default: 0.
readBigInts <boolean> If true, integer fields are read as JavaScript BigInt values. If false,
integer fields are read as JavaScript numbers. Default: false.
returnArrays <boolean> If true, query results are returned as arrays instead of objects.
Default: false.
allowBareNamedParameters <boolean> If true, allows binding named parameters without the prefix
character (e.g., foo instead of :foo). Default: true.
allowUnknownNamedParameters <boolean> If true, unknown named parameters are ignored when binding.
If false, an exception is thrown for unknown named parameters. Default: false.
Constructs a new DatabaseSync instance.
database.aggregate(name, options)#
Added in: v22.16.0
Registers a new aggregate function with the SQLite database. This method is a wrapper around
sqlite3_create_window_function().
name <string> The name of the SQLite function to create.
options <Object> Function configuration settings.
deterministic <boolean> If true, the SQLITE_DETERMINISTIC flag is
set on the created function. Default: false.
directOnly <boolean> If true, the SQLITE_DIRECTONLY flag is set on
the created function. Default: false.
useBigIntArguments <boolean> If true, integer arguments to options.step and options.inverse
are converted to BigInts. If false, integer arguments are passed as
JavaScript numbers. Default: false.
varargs <boolean> If true, options.step and options.inverse may be invoked with any number of
arguments (between zero and SQLITE_MAX_FUNCTION_ARG). If false,
inverse and step must be invoked with exactly length arguments.
Default: false.
start <number> | <string> | <null> | <Array> | <Object> | <Function> The identity
value for the aggregation function. This value is used when the aggregation
function is initialized. When a <Function> is passed the identity will be its return value.
step <Function> The function to call for each row in the aggregation. The
function receives the current state and the row value. The return value of
this function should be the new state.
result <Function> The function to call to get the result of the
aggregation. The function receives the final state and should return the
result of the aggregation.
inverse <Function> When this function is provided, the aggregate method will work as a window function.
The function receives the current state and the dropped row value. The return value of this function should be the
new state.
When used as a window function, the result function will be called multiple times.
const { DatabaseSync } = require('node:sqlite');
const db = new DatabaseSync(':memory:');
db.exec(`
CREATE TABLE t3(x, y);
INSERT INTO t3 VALUES ('a', 4),
('b', 5),
('c', 3),
('d', 8),
('e', 1);
`);
db.aggregate('sumint', {
start: 0,
step: (acc, value) => acc + value,
});
db.prepare('SELECT sumint(y) as total FROM t3').get(); import { DatabaseSync } from 'node:sqlite';
const db = new DatabaseSync(':memory:');
db.exec(`
CREATE TABLE t3(x, y);
INSERT INTO t3 VALUES ('a', 4),
('b', 5),
('c', 3),
('d', 8),
('e', 1);
`);
db.aggregate('sumint', {
start: 0,
step: (acc, value) => acc + value,
});
db.prepare('SELECT sumint(y) as total FROM t3').get();
database.close()#
Added in: v22.5.0
Closes the database connection. An exception is thrown if the database is not
open. This method is a wrapper around sqlite3_close_v2().
database.loadExtension(path)#
Added in: v22.13.0
path <string> The path to the shared library to load.
Loads a shared library into the database connection. This method is a wrapper
around sqlite3_load_extension(). It is required to enable the
allowExtension option when constructing the DatabaseSync instance.
database.enableLoadExtension(allow)#
Added in: v22.13.0
allow <boolean> Whether to allow loading extensions.
Enables or disables the loadExtension SQL function, and the loadExtension()
method. When allowExtension is false when constructing, you cannot enable
loading extensions for security reasons.
database.location([dbName])#
Added in: v22.16.0
dbName <string> Name of the database. This can be 'main' (the default primary database) or any other
database that has been added with ATTACH DATABASE Default: 'main'.
- Returns: <string> | <null> The location of the database file. When using an in-memory database,
this method returns null.
This method is a wrapper around sqlite3_db_filename()
database.exec(sql)#
Added in: v22.5.0
This method allows one or more SQL statements to be executed without returning
any results. This method is useful when executing SQL statements read from a
file. This method is a wrapper around sqlite3_exec().
database.function(name[, options], function)#
Added in: v22.13.0
name <string> The name of the SQLite function to create.
options <Object> Optional configuration settings for the function. The
following properties are supported:
deterministic <boolean> If true, the SQLITE_DETERMINISTIC flag is
set on the created function. Default: false.
directOnly <boolean> If true, the SQLITE_DIRECTONLY flag is set on
the created function. Default: false.
useBigIntArguments <boolean> If true, integer arguments to function
are converted to BigInts. If false, integer arguments are passed as
JavaScript numbers. Default: false.
varargs <boolean> If true, function may be invoked with any number of
arguments (between zero and SQLITE_MAX_FUNCTION_ARG). If false,
function must be invoked with exactly function.length arguments.
Default: false.
function <Function> The JavaScript function to call when the SQLite
function is invoked. The return value of this function should be a valid
SQLite data type: see Type conversion between JavaScript and SQLite.
The result defaults to NULL if the return value is undefined.
This method is used to create SQLite user-defined functions. This method is a
wrapper around sqlite3_create_function_v2().
database.isOpen#
Added in: v22.15.0
- Type: <boolean> Whether the database is currently open or not.
database.isTransaction#
Added in: v22.16.0
database.open()#
Added in: v22.5.0
Opens the database specified in the path argument of the DatabaseSync
constructor. This method should only be used when the database is not opened via
the constructor. An exception is thrown if the database is already open.
database.createSession([options])#
Added in: v22.12.0
options <Object> The configuration options for the session.
table <string> A specific table to track changes for. By default, changes to all tables are tracked.
db <string> Name of the database to track. This is useful when multiple databases have been added using ATTACH DATABASE. Default: 'main'.
- Returns: <Session> A session handle.
Creates and attaches a session to the database. This method is a wrapper around sqlite3session_create() and sqlite3session_attach().
database.applyChangeset(changeset[, options])#
Added in: v22.12.0
changeset <Uint8Array> A binary changeset or patchset.
options <Object> The configuration options for how the changes will be applied.
-
filter <Function> Skip changes that, when targeted table name is supplied to this function, return a truthy value.
By default, all changes are attempted.
-
onConflict <Function> A function that determines how to handle conflicts. The function receives one argument,
which can be one of the following values:
SQLITE_CHANGESET_DATA: A DELETE or UPDATE change does not contain the expected "before" values.
SQLITE_CHANGESET_NOTFOUND: A row matching the primary key of the DELETE or UPDATE change does not exist.
SQLITE_CHANGESET_CONFLICT: An INSERT change results in a duplicate primary key.
SQLITE_CHANGESET_FOREIGN_KEY: Applying a change would result in a foreign key violation.
SQLITE_CHANGESET_CONSTRAINT: Applying a change results in a UNIQUE, CHECK, or NOT NULL constraint
violation.
The function should return one of the following values:
SQLITE_CHANGESET_OMIT: Omit conflicting changes.
SQLITE_CHANGESET_REPLACE: Replace existing values with conflicting changes (only valid with
SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT conflicts).
SQLITE_CHANGESET_ABORT: Abort on conflict and roll back the database.
When an error is thrown in the conflict handler or when any other value is returned from the handler,
applying the changeset is aborted and the database is rolled back.
Default: A function that returns SQLITE_CHANGESET_ABORT.
- Returns: <boolean> Whether the changeset was applied successfully without being aborted.
An exception is thrown if the database is not
open. This method is a wrapper around sqlite3changeset_apply().
const sourceDb = new DatabaseSync(':memory:');
const targetDb = new DatabaseSync(':memory:');
sourceDb.exec('CREATE TABLE data(key INTEGER PRIMARY KEY, value TEXT)');
targetDb.exec('CREATE TABLE data(key INTEGER PRIMARY KEY, value TEXT)');
const session = sourceDb.createSession();
const insert = sourceDb.prepare('INSERT INTO data (key, value) VALUES (?, ?)');
insert.run(1, 'hello');
insert.run(2, 'world');
const changeset = session.changeset();
targetDb.applyChangeset(changeset);
database[Symbol.dispose]()#
Added in: v22.15.0
Closes the database connection. If the database connection is already closed
then this is a no-op.
Class: Session#
Added in: v22.12.0
session.changeset()#
Added in: v22.12.0
- Returns: <Uint8Array> Binary changeset that can be applied to other databases.
Retrieves a changeset containing all changes since the changeset was created. Can be called multiple times.
An exception is thrown if the database or the session is not open. This method is a wrapper around sqlite3session_changeset().
session.patchset()#
Added in: v22.12.0
- Returns: <Uint8Array> Binary patchset that can be applied to other databases.
Similar to the method above, but generates a more compact patchset. See Changesets and Patchsets
in the documentation of SQLite. An exception is thrown if the database or the session is not open. This method is a
wrapper around sqlite3session_patchset().
session.close().#
Closes the session. An exception is thrown if the database or the session is not open. This method is a
wrapper around sqlite3session_delete().
Class: StatementSync#
Added in: v22.5.0
This class represents a single prepared statement. This class cannot be
instantiated via its constructor. Instead, instances are created via the
database.prepare() method. All APIs exposed by this class execute
synchronously.
A prepared statement is an efficient binary representation of the SQL used to
create it. Prepared statements are parameterizable, and can be invoked multiple
times with different bound values. Parameters also offer protection against
SQL injection attacks. For these reasons, prepared statements are preferred
over hand-crafted SQL strings when handling user input.
statement.all([namedParameters][, ...anonymousParameters])#
namedParameters <Object> An optional object used to bind named parameters.
The keys of this object are used to configure the mapping.
...anonymousParameters <null> | <number> | <bigint> | <string> | <Buffer> | <TypedArray> | <DataView> Zero or
more values to bind to anonymous parameters.
- Returns: <Array> An array of objects. Each object corresponds to a row
returned by executing the prepared statement. The keys and values of each
object correspond to the column names and values of the row.
This method executes a prepared statement and returns all results as an array of
objects. If the prepared statement does not return any results, this method
returns an empty array. The prepared statement parameters are bound using
the values in namedParameters and anonymousParameters.
statement.columns()#
Added in: v22.16.0
This method is used to retrieve information about the columns returned by the
prepared statement.
statement.expandedSQL#
Added in: v22.5.0
- Type: <string> The source SQL expanded to include parameter values.
The source SQL text of the prepared statement with parameter
placeholders replaced by the values that were used during the most recent
execution of this prepared statement. This property is a wrapper around
sqlite3_expanded_sql().
statement.get([namedParameters][, ...anonymousParameters])#
namedParameters <Object> An optional object used to bind named parameters.
The keys of this object are used to configure the mapping.
...anonymousParameters <null> | <number> | <bigint> | <string> | <Buffer> | <TypedArray> | <DataView> Zero or
more values to bind to anonymous parameters.
- Returns: <Object> | <undefined> An object corresponding to the first row returned
by executing the prepared statement. The keys and values of the object
correspond to the column names and values of the row. If no rows were returned
from the database then this method returns
undefined.
This method executes a prepared statement and returns the first result as an
object. If the prepared statement does not return any results, this method
returns undefined. The prepared statement parameters are bound using the
values in namedParameters and anonymousParameters.
statement.iterate([namedParameters][, ...anonymousParameters])#
namedParameters <Object> An optional object used to bind named parameters.
The keys of this object are used to configure the mapping.
...anonymousParameters <null> | <number> | <bigint> | <string> | <Buffer> | <TypedArray> | <DataView> Zero or
more values to bind to anonymous parameters.
- Returns: <Iterator> An iterable iterator of objects. Each object corresponds to a row
returned by executing the prepared statement. The keys and values of each
object correspond to the column names and values of the row.
This method executes a prepared statement and returns an iterator of
objects. If the prepared statement does not return any results, this method
returns an empty iterator. The prepared statement parameters are bound using
the values in namedParameters and anonymousParameters.
statement.run([namedParameters][, ...anonymousParameters])#
namedParameters <Object> An optional object used to bind named parameters.
The keys of this object are used to configure the mapping.
...anonymousParameters <null> | <number> | <bigint> | <string> | <Buffer> | <TypedArray> | <DataView> Zero or
more values to bind to anonymous parameters.
- Returns: <Object>
changes <number> | <bigint> The number of rows modified, inserted, or deleted
by the most recently completed INSERT, UPDATE, or DELETE statement.
This field is either a number or a BigInt depending on the prepared
statement's configuration. This property is the result of
sqlite3_changes64().
lastInsertRowid <number> | <bigint> The most recently inserted rowid. This
field is either a number or a BigInt depending on the prepared statement's
configuration. This property is the result of
sqlite3_last_insert_rowid().
This method executes a prepared statement and returns an object summarizing the
resulting changes. The prepared statement parameters are bound using the
values in namedParameters and anonymousParameters.
statement.setAllowBareNamedParameters(enabled)#
Added in: v22.5.0
enabled <boolean> Enables or disables support for binding named parameters
without the prefix character.
The names of SQLite parameters begin with a prefix character. By default,
node:sqlite requires that this prefix character is present when binding
parameters. However, with the exception of dollar sign character, these
prefix characters also require extra quoting when used in object keys.
To improve ergonomics, this method can be used to also allow bare named
parameters, which do not require the prefix character in JavaScript code. There
are several caveats to be aware of when enabling bare named parameters:
- The prefix character is still required in SQL.
- The prefix character is still allowed in JavaScript. In fact, prefixed names
will have slightly better binding performance.
- Using ambiguous named parameters, such as
$k and @k, in the same prepared
statement will result in an exception as it cannot be determined how to bind
a bare name.
statement.setAllowUnknownNamedParameters(enabled)#
Added in: v22.15.0
enabled <boolean> Enables or disables support for unknown named parameters.
By default, if an unknown name is encountered while binding parameters, an
exception is thrown. This method allows unknown named parameters to be ignored.
statement.setReturnArrays(enabled)#
Added in: v22.16.0
enabled <boolean> Enables or disables the return of query results as arrays.
When enabled, query results returned by the all(), get(), and iterate() methods will be returned as arrays instead
of objects.
statement.setReadBigInts(enabled)#
Added in: v22.5.0
enabled <boolean> Enables or disables the use of BigInts when reading
INTEGER fields from the database.
When reading from the database, SQLite INTEGERs are mapped to JavaScript
numbers by default. However, SQLite INTEGERs can store values larger than
JavaScript numbers are capable of representing. In such cases, this method can
be used to read INTEGER data using JavaScript BigInts. This method has no
impact on database write operations where numbers and BigInts are both
supported at all times.
statement.sourceSQL#
Added in: v22.5.0
- Type: <string> The source SQL used to create this prepared statement.
The source SQL text of the prepared statement. This property is a
wrapper around sqlite3_sql().
Type conversion between JavaScript and SQLite#
When Node.js writes to or reads from SQLite it is necessary to convert between
JavaScript data types and SQLite's data types. Because JavaScript supports
more data types than SQLite, only a subset of JavaScript types are supported.
Attempting to write an unsupported data type to SQLite will result in an
exception.
sqlite.backup(sourceDb, destination[, options])#
Added in: v22.16.0
sourceDb <DatabaseSync> The database to backup. The source database must be open.
destination <string> The path where the backup will be created. If the file already exists, the contents will be
overwritten.
options <Object> Optional configuration for the backup. The
following properties are supported:
source <string> Name of the source database. This can be 'main' (the default primary database) or any other
database that have been added with ATTACH DATABASE Default: 'main'.
target <string> Name of the target database. This can be 'main' (the default primary database) or any other
database that have been added with ATTACH DATABASE Default: 'main'.
rate <number> Number of pages to be transmitted in each batch of the backup. Default: 100.
progress <Function> An optional callback function that will be called after each backup step. The argument passed
to this callback is an <Object> with remainingPages and totalPages properties, describing the current progress
of the backup operation.
- Returns: <Promise> A promise that fulfills with the total number of backed-up pages upon completion, or rejects if an
error occurs.
This method makes a database backup. This method abstracts the sqlite3_backup_init(), sqlite3_backup_step()
and sqlite3_backup_finish() functions.
The backed-up database can be used normally during the backup process. Mutations coming from the same connection - same
<DatabaseSync> - object will be reflected in the backup right away. However, mutations from other connections will cause
the backup process to restart.
const { backup, DatabaseSync } = require('node:sqlite');
(async () => {
const sourceDb = new DatabaseSync('source.db');
const totalPagesTransferred = await backup(sourceDb, 'backup.db', {
rate: 1,
progress: ({ totalPages, remainingPages }) => {
console.log('Backup in progress', { totalPages, remainingPages });
},
});
console.log('Backup completed', totalPagesTransferred);
})();import { backup, DatabaseSync } from 'node:sqlite';
const sourceDb = new DatabaseSync('source.db');
const totalPagesTransferred = await backup(sourceDb, 'backup.db', {
rate: 1,
progress: ({ totalPages, remainingPages }) => {
console.log('Backup in progress', { totalPages, remainingPages });
},
});
console.log('Backup completed', totalPagesTransferred);
sqlite.constants#
Added in: v22.13.0
An object containing commonly used constants for SQLite operations.
SQLite constants#
The following constants are exported by the sqlite.constants object.
Conflict resolution constants#
One of the following constants is available as an argument to the onConflict
conflict resolution handler passed to database.applyChangeset(). See also
Constants Passed To The Conflict Handler in the SQLite documentation.
| Constant |
Description |
SQLITE_CHANGESET_DATA |
The conflict handler is invoked with this constant when processing a DELETE or UPDATE change if a row with the required PRIMARY KEY fields is present in the database, but one or more other (non primary-key) fields modified by the update do not contain the expected "before" values. |
SQLITE_CHANGESET_NOTFOUND |
The conflict handler is invoked with this constant when processing a DELETE or UPDATE change if a row with the required PRIMARY KEY fields is not present in the database. |
SQLITE_CHANGESET_CONFLICT |
This constant is passed to the conflict handler while processing an INSERT change if the operation would result in duplicate primary key values. |
SQLITE_CHANGESET_CONSTRAINT |
If foreign key handling is enabled, and applying a changeset leaves the database in a state containing foreign key violations, the conflict handler is invoked with this constant exactly once before the changeset is committed. If the conflict handler returns SQLITE_CHANGESET_OMIT, the changes, including those that caused the foreign key constraint violation, are committed. Or, if it returns SQLITE_CHANGESET_ABORT, the changeset is rolled back. |
SQLITE_CHANGESET_FOREIGN_KEY |
If any other constraint violation occurs while applying a change (i.e. a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is invoked with this constant. |
One of the following constants must be returned from the onConflict conflict
resolution handler passed to database.applyChangeset(). See also
Constants Returned From The Conflict Handler in the SQLite documentation.
| Constant |
Description |
SQLITE_CHANGESET_OMIT |
Conflicting changes are omitted. |
SQLITE_CHANGESET_REPLACE |
Conflicting changes replace existing values. Note that this value can only be returned when the type of conflict is either SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. |
SQLITE_CHANGESET_ABORT |
Abort when a change encounters a conflict and roll back database. |