mysql-js-stored-procedures

Write JavaScript stored procedures and functions in Percona Server for MySQL.

1|1|Updated May 29, 2026

Search Tags:#javascript #mysql #sandbox #stored-procedures #privileges #js_lang #tech-preview

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npx skills add https://github.com/Percona-Lab/skills --skill mysql-js-stored-procedures

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Please help me install this Agent Skill.
Skill: mysql-js-stored-procedures
Source: https://github.com/Percona-Lab/skills/tree/main/mysql-js-stored-procedures
Command: npx skills add https://github.com/Percona-Lab/skills --skill mysql-js-stored-procedures

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

The js_lang component lets you write stored functions and procedures in JavaScript (V8 engine) instead of SQL/PSM, addressing scenarios where complex logic is more concise in JavaScript. It is tech preview in Percona Server 8.4 and executes in a sandbox with no file or network I/O, requiring installation of the component and the appropriate privileges.

Core Features & Use Cases

Write stored routines in JavaScript using the V8 engine, enabling clearer implementation for complex logic.
Sandbox execution with no file or network I/O; restricted environment to protect the database server.
Requires INSTALL COMPONENT 'file://component_js_lang' and the CREATE_JS_ROUTINE privilege; supports CREATE FUNCTION and CREATE PROCEDURE with LANGUAGE JS.

Quick Start

Install the component and grant the CREATE_JS_ROUTINE privilege, then create a JS-based routine using the LANGUAGE JS syntax.

Frequently Asked Questions about mysql-js-stored-procedures

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

Can I write stored procedures in JavaScript inside MySQL?▼

Yes, you can write stored procedures in JavaScript inside MySQL using the js_lang component in Percona Server for MySQL 8.4. It uses the V8 engine, allowing clearer implementation for complex logic compared to standard SQL/PSM.

How do I enable JavaScript stored routines in Percona Server for MySQL?▼

To enable JavaScript stored routines, install the js_lang component by running INSTALL COMPONENT 'file://component_js_lang' and grant the CREATE_JS_ROUTINE privilege to your database users.

Does Percona Server for MySQL 8.4 support JavaScript functions?▼

Percona Server for MySQL 8.4 supports JavaScript functions and procedures as a tech-preview feature. You define them using the standard CREATE FUNCTION or CREATE PROCEDURE syntax with the LANGUAGE JS clause.

What are the limitations of JavaScript stored procedures in MySQL?▼

JavaScript stored procedures run in a sandbox environment with no file or network I/O access. This restricted environment protects the database server, meaning your JS routines cannot make external network calls or read local files.

What privileges do I need to create JavaScript stored procedures in MySQL?▼

You need the CREATE_JS_ROUTINE privilege to define JavaScript stored procedures and functions in MySQL. This specific privilege controls the ability to use the LANGUAGE JS syntax for routine creation.