It will also insert a new row into this table. Below is an example of how to create a new table named users with columns for ID, name, phone number, and address in our database. The parameter stmt is, of course, your SQL statement. The syntax is as written below: db.run(stmt) With SQL.js, you can easily run a statement without reading its results. Running SQL statementsĪn SQL statement could be a request to create or retrieve a piece of information in the database or to perform an operation on existing data. In the code above, we used the built-in Node.js fs and path modules to read our existing sample.sqlite file. Create a new database with our existing sample.sqlite file Let filebuffer = fs.readFileSync("/path/to/sample.sqlite") Let initSqlJs = require("./sql-wasm.js") sqlite file like below: let fs = require("fs") For example, in Node.js we can load an existing. It’s worth noting that the SQL.Database() method accepts an optional parameter data, which must be a Uint8Array representing a SQLite database file. The code below creates a new database: const db = new SQL.Database() Now that we’ve followed all the required steps to install and initialize SQL.js, let’s dive into its usage. Writing SQL queries and prepared statements So our code will look like this: var initSqlJs = require("./sql-wasm.js") To install it, you can simply run: npm install sql.jsĪlternatively, you can download sql-wasm.js and sql-wasm.wasm from the previous links and use the Node.js require function to load them in your project.Īlso, in a Node-based project, you can skip the locateFile method to load the sql-wasm.wasm file because it will load automatically if it’s in the same folder as the current file you are working on. Installing SQL.js in a Node-based project is pretty straightforward as well. In the code block above, we used initSqlJs to load the Wasm binary file asynchronously and initialize SQL.js after loading the required files. LocateFile: () => "/path/to/downloaded/sql-wasm.wasm", You can download this file online and use the locateFile function to load the file in your webpage, like so: wasm file in addition to the JavaScript library. You can get started by including the CDN or downloading the source files and linking them to your markup page.īy default, SQL.js uses WebAssembly and needs to load a. Integrating SQL.js into a new client-side-based project is super easy. However, you can import any existing SQLite file and export the created database as a JavaScript typed array. This is because SQL.js uses a virtual database file stored in the browser memory. Read it again: all changes made to your database will cease to exist when you reload your browser. Sqlstr += "INSERT INTO hello VALUES (0, 'hello') "īut there is an important con as well: changes to your database when using SQL.js are not persistent. And SQL.js provides support for executing single SQL strings that contain multiple statements, as seen below: sqlstr = "CREATE TABLE tableName(colA, colB) " Getting started with SQL.js is as easy as installing jQuery in an existing HTML project. It’s easier to set up than MySQL, PostgreSQL, and others, which require third-party software to use. It’s built for and works entirely on the client side, which means it won’t require any server-side processes to work. With this feature, you can easily bring in an existing SQLite database to use in SQL.js and also convert a database created in SQL.js to SQLite. This library also uses Emscripten to compile SQLite to WebAssembly (Wasm). It uses a virtual database file stored in the browser memory, so it doesn’t persist the changes made to the database. SQL.js is a JavaScript library that allows you to create and query a relational database entirely in the browser.
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