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2022-10-30
用于Node.js应用程序的SQLite客户端库和基于SQL的迁移API
SQLite Client for Node.js Apps
A wrapper library written in Typescript with ZERO dependencies that adds ES6 promises and SQL-based migrations API to sqlite3 (docs).
note v4 of sqlite has breaking changes compared to v3! Please see CHANGELOG.md for more details.
InstallationInstall sqlite3Install sqlite UsageOpening the databaseWithout cachingWith cachingEnable verbose / debug modeTracing SQL errorsWith a custom driverOpening multiple databasesopen config params ExamplesCreating a table and inserting dataGetting a single rowGetting many rowsInserting rowsUpdating rowsPrepared statementeach()Get the driver instanceClosing the database ES6 tagged template stringsMigrations Typescript tricksImport interfaces from sqliteSpecify typings for a specific database driverUse generics to get better typings on your rowsGet exampleAll example API DocumentationManagement ToolsAlternative SQLite librariesReferencesSupportLicense
Installation
Install sqlite3
Most people who use this library will use sqlite3 as the database driver.
Any library that conforms to the sqlite3 (API) should also work.
$ npm install sqlite3 --save
Install sqlite
# v4 of sqlite is targeted for nodejs 10 and on.$ npm install sqlite --save# If you need a legacy version for an older version of nodejs# install v3 instead, and look at the v3 branch readme for usage details$ npm install sqlite@3 --save
Usage
This module has the same API as the original sqlite3 library (docs), except that all its API methods return ES6 Promises and do not accept callback arguments (with the exception of each()).
Opening the database
Without caching
import sqlite3 from 'sqlite3'import { open } from 'sqlite'// this is a top-level await (async () => { // open the database const db = await open({ filename: '/tmp/database.db', driver: sqlite3.Database })})()
or
import sqlite3 from 'sqlite3'import { open } from 'sqlite'open({ filename: '/tmp/database.db', driver: sqlite3.Database}).then((db) => { // do your thing})
or
import sqlite3 from 'sqlite3'import { open } from 'sqlite'// you would have to import / invoke this in another fileexport async function openDb () { return open({ filename: '/tmp/database.db', driver: sqlite3.Database })}
With caching
If you want to enable the database object cache
import sqlite3 from 'sqlite3'import { open } from 'sqlite'(async () => { const db = await open({ filename: '/tmp/database.db', driver: sqlite3.cached.Database })})()
Enable verbose / debug mode
import sqlite3 from 'sqlite3'sqlite3.verbose()
Tracing SQL errors
For more info, see this doc.
db.on('trace', (data) => { })
With a custom driver
You can use an alternative library to sqlite3 as long as it conforms to the sqlite3 API.
For example, using sqlite3-offline:
import sqlite3Offline from 'sqlite3-offline'import { open } from 'sqlite'(async () => { const db = await open({ filename: '/tmp/database.db', driver: sqlite3Offline.Database })})()
Opening multiple databases
import sqlite3 from 'sqlite3'import { open } from 'sqlite'(async () => { const [db1, db2] = await Promise.all([ open({ filename: '/tmp/database.db', driver: sqlite3.Database }), open({ filename: '/tmp/database2.db', driver: sqlite3.Database }), ]) await db1.migrate({ migrationsPath: '...' }) await db2.migrate({ migrationsPath: '...' })})()
open config params
// db is an instance of `sqlite#Database`// which is a wrapper around `sqlite3#Database`const db = await open({ /** * Valid values are filenames, ":memory:" for an anonymous in-memory * database and an empty string for an anonymous disk-based database. * Anonymous databases are not persisted and when closing the database * handle, their contents are lost. */ filename: string /** * One or more of sqlite3.OPEN_READONLY, sqlite3.OPEN_READWRITE and * sqlite3.OPEN_CREATE. The default value is OPEN_READWRITE | OPEN_CREATE. */ mode?: number /** * The database driver. Most will install `sqlite3` and use the `Database` class from it. * As long as the library you are using conforms to the `sqlite3` API, you can use it as * the driver. * * @example * * ``` * import sqlite from 'sqlite3' * * const driver = sqlite.Database * ``` */ driver: any})
Examples
See the src/**/__tests__ directory for more example usagesSee the docs/ directory for full documentation.Also visit the sqlite3 library API docs
Creating a table and inserting data
await db.exec('CREATE TABLE tbl (col TEXT)')await db.exec('INSERT INTO tbl VALUES ("test")')
Getting a single row
const result = await db.get('SELECT col FROM tbl WHERE col = ?', 'test')// { col: 'test' }
const result = await db.get('SELECT col FROM tbl WHERE col = ?', ['test'])// { col: 'test' }
const result = await db.get('SELECT col FROM tbl WHERE col = :test', { ':test': 'test'})// { col: 'test' }
Getting many rows
const result = await db.all('SELECT col FROM tbl')// [{ col: 'test' }]
Inserting rows
const result = await db.run( 'INSERT INTO tbl (col) VALUES (?)', 'foo')/*{ // row ID of the inserted row lastID: 1, // instance of `sqlite#Statement` // which is a wrapper around `sqlite3#Statement` stmt:
const result = await db.run('INSERT INTO tbl(col) VALUES (:col)', { ':col': 'something'})
Updating rows
const result = await db.run( 'UPDATE tbl SET col = ? WHERE col = ?', 'foo', 'test')/*{ // number of rows changed changes: 1, // instance of `sqlite#Statement` // which is a wrapper around `sqlite3#Statement` stmt:
Prepared statement
// stmt is an instance of `sqlite#Statement`// which is a wrapper around `sqlite3#Statement`const stmt = await db.prepare('SELECT col FROM tbl WHERE 1 = ? AND 5 = ?5')await stmt.bind({ 1: 1, 5: 5 })let result = await stmt.get()// { col: 'some text' }
const stmt = await db.prepare( 'SELECT col FROM tbl WHERE 13 = @thirteen ORDER BY col DESC')const result = await stmt.all({ '@thirteen': 13 })
each()
each() is a bit different compared to the other operations.
The function signature looks like this:
async each (sql, [...params], callback)
callback(err, row) is triggered when the database has a row to returnThe promise resolves when all rows have returned with the number or rows returned.
const rowsCount = await db.each( 'SELECT col FROM tbl WHERE ROWID = ?', [2], (err, row) => { if (err) { throw err } // row = { col: 'other thing' } })// rowsCount = 1
Get the driver instance
Useful if you need to call methods that are not supported yet.
const rawDb = db.getDatabaseInstance()const rawStatement = stmt.getStatementInstance()
Closing the database
await db.close()
ES6 tagged template strings
This module is compatible with sql-template-strings.
import SQL from 'sql-template-strings'const book = 'harry potter';const author = 'J. K. Rowling';const data = await db.all(SQL`SELECT author FROM books WHERE name = ${book} AND author = ${author}`);
Migrations
This module comes with a lightweight migrations API that works with SQL-based migration files
With default configuration, you can create a migrations/ directory in your project with SQL files, and call the migrate() method to run the SQL in the directory against the database.
See this project's migrations/ folder for examples.
await db.migrate({ /** * If true, will force the migration API to rollback and re-apply the latest migration over * again each time when Node.js app launches. */ force?: boolean /** * Migrations table name. Default is 'migrations' */ table?: string /** * Path to the migrations folder. Default is `path.join(process.cwd(), 'migrations')` */ migrationsPath?: string})
Typescript tricks
Import interfaces from sqlite
import { ISqlite, IMigrate } from 'sqlite'
See the definitions for more details.
Specify typings for a specific database driver
// Assuming you have @types/sqlite3 installedimport sqlite3 from 'sqlite3'// sqlite3.Database, sqlite3.Statement is the default if no explicit generic is specifiedawait open
Use generics to get better typings on your rows
Most methods allow for the use of generics to specify the data type of your returned data. This allows your IDE to perform better autocomplete and the typescript compiler to perform better static type analysis.
Get example
interface Row { col: string}// result will be of type Row, allowing Typescript supported IDEs to autocomplete on the properties!const result = await db.get
All example
interface Row { col: string}// Result is an array of rows, you can now have array-autocompletion dataconst result = await db.all
API Documentation
See the docs directory for full documentation.
Management Tools
Beekeeper Studio: Open Source SQL Editor and Database ManagerDB Browser for SQLite: Desktop-based browser.datasette: Datasette is a tool for exploring and publishing data. Starts up a server that provides a web interface to your SQLite data.SQLite Studio: A free, open source, multi-platform SQLite database manager written in C++, with use of Qt framework.HeidiSQL: Full-featured database editor.DBeaver: Full-featured multi-platform database tool and designer.
Alternative SQLite libraries
This library and the library it primarily supports, sqlite3, may not be the best library that fits your use-case. You might want to try these other SQLite libraries:
better-sqlite3: Totes itself as the fastest and simplest library for SQLite3 in Node.js.sql.js: SQLite compiled to Webassembly.sqlite3-offline: Offers pre-compiled sqlite3 binaries if your machine cannot compile it. Should be mostly compatible with this library.
If you know of any others, feel free to open a PR to add them to the list.
References
Using SQLite with Node.js for Rapid Prototyping on Medium.comSQLite Documentation, e.g. SQL Syntax, Data Types etc. on SQLite.orgES6 tagged sql-template-strings.
Support
Join #node-sqlite chat room on Gitter to stay up to date regarding the projectJoin #sqlite IRC chat room on Freenode about general discussion about SQLite
License
The MIT License © 2020-present Kriasoft / Theo Gravity. All rights reserved.
Made with ♥ by Konstantin Tarkus (@koistya), Theo Gravity and contributors
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