SchemaFleet for VS Code

Compare, diagram and sync database schemas across your whole fleet of databases, without leaving VS Code.

SchemaFleet compares one source database with up to 300 target databases at once, such as every tenant of a multi-tenant application. It groups the targets that need exactly the same changes, lets you review, rewrite and approve each change, and applies the approved ones one database at a time. Works with MySQL, MariaDB, PostgreSQL and Microsoft SQL Server.

Free to use. Nothing else to install: the schemafleet program (v1.3.0) is included for Windows, macOS and Linux.

Highlights

Compare a fleet. Pick the targets one by one, or many databases on a server at once, and save them as a compare set to run again later. Targets that need the same changes share a sync number, so 300 tenants become a handful of change lists to review.
Review before anything changes. Every change shows its SQL and what it risks (destructive changes and warnings are marked). Approve or Revoke each one, or rewrite it in place; only approved changes run.
Apply safely. Approved changes run one database at a time, in plan order, with progress and the time left. Each database is compared again first and skipped if it changed since you reviewed it.
Diagram and browse. An interactive diagram of tables and views, and an object browser for tables, views, stored procedures, functions, triggers and events, with the SQL of any object one click away.
Copy or download SQL of a sync number: all statements, or one type of object at a time.
Your connections in the sidebar. The SchemaFleet sidebar lists your saved connections, each with its compare sets. Select a connection to open it, or a compare set to open its connection with the set ready to compare.

Getting started

Select the SchemaFleet icon in the Activity Bar (or run SchemaFleet: Open from the Command Palette, Ctrl+Shift+P).
Add connection (the + of the sidebar): enter the database details or paste a connection URL, select Test connection, then Connect. Saved connections then appear in the sidebar.
In Compare, add the target databases and select Compare.
Open a sync number, review its changes, approve them, and select Apply approved.

Comparing never changes a database. Only the changes you approve are applied, and only when you select Apply.

Supported databases

MySQL
MariaDB
PostgreSQL
Microsoft SQL Server 2016 SP1 or later, and Azure SQL Database: tables, views, stored procedures, functions, triggers (also INSTEAD OF triggers of views), sequences, synonyms and alias types, in every schema of a database

SQLite is not supported by the included program.

Privacy and security

SchemaFleet runs on your computer. It connects only to the databases you add and sends no data, usage or telemetry to naga4u or anyone else.
Connections are encrypted whenever the database server supports TLS.
Passwords are never kept in a file: on Windows they are kept in Windows Credential Manager, and on macOS in the Keychain. On Linux they are asked for once per VS Code session.
The interface is served only to this computer and protected by a session token.

Commands

Command	What it does
SchemaFleet: Open	Opens SchemaFleet.
SchemaFleet: Add Connection	Opens SchemaFleet to add a connection.
SchemaFleet: Refresh Connections	Reloads the saved connections of the sidebar.
SchemaFleet: Open in New Window	Opens it in a window of its own.
SchemaFleet: Open in Editor Tab	Opens it in a tab of the current window.
SchemaFleet: Open in Browser	Opens it in your web browser.
SchemaFleet: Restart Server	Restarts the SchemaFleet server.
SchemaFleet: Show Saved Connections Folder	Opens the folder holding your connections and compare sets.
SchemaFleet: Show Log	Shows the output of the SchemaFleet server.

Settings

Setting	Default	Description
`schemafleet.openIn`	`editorTab`	Where SchemaFleet opens: `editorTab`, `newWindow` or `browser`.
`schemafleet.openOnSidebarClick`	`true`	Open SchemaFleet when its Activity Bar icon is selected.
`schemafleet.binaryPath`	(empty)	Use another `schemafleet` program instead of the included one.

Where your data is kept

Saved connections and compare sets stay on this computer until you delete them in SchemaFleet or uninstall the extension. They are kept across VS Code restarts and updates.

What	Where
Connections and compare sets	`%APPDATA%\schemafleet-vscode\` (Windows) `~/Library/Application Support/schemafleet-vscode/` (macOS) `~/.config/schemafleet-vscode/` (Linux)
Passwords	Windows Credential Manager (Windows) or the login keychain (macOS), as `SchemaFleet/<connection id>`

Uninstalling the extension removes them; VS Code runs this clean-up the next time it starts.

Limits

The extension runs on your computer, also when VS Code is connected to a remote machine (SSH, WSL, containers): databases must be reachable from your computer.
SQL Server: the user needs the VIEW DEFINITION permission to read views, procedures, functions and triggers. XML, spatial and full-text indexes, table types and database triggers are not read. A column cannot be turned into an IDENTITY column or back; such a change is reported, not planned.

License

SchemaFleet is free to install and use, for personal and commercial work, on any number of your devices. Features marked Pro, when there are any, need a paid license from naga4u. You may not copy, modify, redistribute or reverse engineer SchemaFleet.

Copyright 2026-present naga4u. The full terms are in LICENSE-NAGA4U, with LICENSE and NOTICE. SchemaFleet includes open source code under the Apache License 2.0 (LICENSE), which keeps the rights that license grants.