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Feroz Shah
Feroz Shah

Posted on Edited on Originally published at migrax.org

Generate and apply database migrations without leaving IntelliJ IDEA

#java #intellij #hibernate #database

You rename a field on a JPA entity. Then you leave the editor to write the SQL, write the rollback script, check which database you are about to change, and run it. The Migrax plugin for IntelliJ IDEA keeps all of that in the IDE. This article follows one renamed field from the edit to the applied migration.

Tested with: Migrax 0.19.0-rc.2, Migrax plugin 0.1.1, IntelliJ IDEA 2026.2.1, Hibernate 6.6.13, PostgreSQL 17. Every screenshot and output below comes from a real run.

IntelliJ IDEA with the project tree, a migration and its rollback script, and the Migrax tool window

The Migrax plugin after a rename: the generated migration and its rollback script, and the tool window with every migration applied.

Install the plugin

In IntelliJ IDEA open Settings > Plugins > Marketplace, search for Migrax and click Install. The plugin is free and works in IntelliJ IDEA Community and Ultimate 2024.2 or newer.

It needs the migrax command. It uses the path in Settings > Tools > Migrax if you set one, then migrax on your PATH, then a copy it downloaded itself. If it finds none, it offers to download the newest release (about 1 MB), checks it against its SHA-256 and unpacks it into the IDE's own folder. A Migrax you installed yourself is never changed.

In a project that does not use Migrax yet, choose Tools > Migrax > Set Up Migrax.... It runs migrax init in the folder you pick and shows what Migrax detected.

The margin icon in the next section needs Migrax 0.18 or newer, which is a release candidate at the time of writing. The rest of the plugin works with Migrax 0.17.

Where we start

This picks up where Renaming columns and tables without losing data started: the same customers and orders project, two migrations applied, and two customers in the table:

      email       | id |     name     |      phone
------------------+----+--------------+------------------
 ada@example.com  |  1 | Ada Lovelace | +44 20 7946 0001
 alan@example.com |  2 | Alan Turing  |
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Rename the field

In Customer, rename name to fullName and give the column its new name:

  @Column(name = "full_name", nullable = false, length = 100)
  String fullName;
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A few seconds after the file changes, a Migrax icon appears in the margin next to the Customer class, and the status bar changes from "Migrax: in sync" to "Migrax: 2 changes". Hover over the icon to see what Migrax found:

Tooltip on the margin icon: 2 changes not in a migration yet, add column customers.full_name, drop column customers.name

Two changes: a new column and a dropped one. Migrax does not know yet that they are the same column.

Click the icon for Generate Migration, or for Show Plan to read the SQL first. They do what migrax generate and migrax plan do in a terminal.

The Migrax menu from the margin icon with Generate Migration and Show Plan

Answer the rename question

Generate Migration asks the question the command line asks:

Dialog: Did you rename customers.name to customers.full_name? with the buttons Renamed and Not Renamed

Answer Renamed and the migration keeps the data. Answer Not Renamed and Migrax drops the old column with its data and adds a new, empty one. Before it drops anything it asks again, and by default it keeps the dropped data in a backup table.

Review the migration

The new migration and its rollback script open in the editor, next to the earlier ones:

Project tree with migrations 0001 to 0003 and a rollback folder, and the 0003 migration above its rollback script

db/migration/0003_rename_customers_name.sql:

-- Generated by Migrax 0.19.0-rc.2 for postgresql

ALTER TABLE customers RENAME COLUMN name TO full_name;
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db/migration/rollback/0003_rename_customers_name.sql:

-- Generated by Migrax 0.19.0-rc.2 for postgresql
-- Rollback for 0003_rename_customers_name.sql. 'migrax rollback' runs it.

ALTER TABLE customers RENAME COLUMN full_name TO name;
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The highlighted line in the migration is a lint finding. Hover over it:

Tooltip MX008 on the RENAME COLUMN statement: application instances still running the old code will fail, with the fix

It is the same message migrax generate prints in a terminal. A rename moves no data, so the statement is fast. The warning is about application instances that still run the old code during a deploy and look for the old column name. The way out it names, migrax generate --zero-downtime, is in the plugin as Generate for Zero Downtime.

Apply the migration

Choose Tools > Migrax > Migrate..., or the Migrate button in the tool window. Before it runs anything, the plugin shows which database it will change and which migrations it will apply:

Dialog: Apply 1 migration to this database? jdbc:postgresql://localhost:5432/shop, 0003_rename_customers_name.sql

Confirm, and the migration runs in a background task, so the editor stays usable. The status bar returns to "Migrax: in sync", and the Migrax tool window lists every migration and its state. Click the status bar entry to open it:

The Migrax tool window, Status tab: three migrations, all applied

The rename moved no data. The same two customers are in the table, under the new column name:

 id |      email       |  full_name   |      phone
----+------------------+--------------+------------------
  1 | ada@example.com  | Ada Lovelace | +44 20 7946 0001
  2 | alan@example.com | Alan Turing  |
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What else is in the tool window

The tool window has four tabs, and its buttons run the other commands. The plugin guide lists every one:

Where What it does
Status tab Every migration and its state: applied, pending, failed, changed or missing
Plan tab The SQL of the next migration, with its lint findings
Lint tab Locking and risky SQL in the pending migrations, or in all of them
Environments tab Every configured database: in sync, pending, drift or unreachable
Roll Back... Shows the database and the newest applied migration, then rolls it back
Drift Lists changes made to the database outside the migrations
Verify Applies every migration to a throwaway database and tests each rollback script, leaving your database alone
Report Opens an HTML report of the schema, the migrations, the lint findings and the drift
Doctor Checks Java, the build, the entities and the database connection

How it works

The plugin contains no migration logic. Every button runs the migrax command in a background task, asks for --json output and draws the answer: the tool window tabs, the margin icon and the underlines. The IDE, your terminal and your CI call the same command, so they give the same result.

What it does not do yet

  • With several Migrax projects below one IDE project, the first one found is used.
  • Migrate and Roll Back work on the database in the project's settings. Other environments show in the Environments tab and are migrated from the command line.
  • Migrate and Roll Back cannot be cancelled once they start, because stopping halfway could leave a migration half applied.
  • The status bar and the margin icons check again about 5 seconds after an entity, migration or settings file changes. That check may build the project, and you can turn it off in Settings > Tools > Migrax.
  • Squash and merge are not in the IDE yet: use migrax squash and migrax merge.
  • Only IntelliJ IDEA is supported. Other JetBrains IDEs are not.

Summary

The Migrax plugin takes an entity edit to an applied migration inside IntelliJ IDEA. The margin icon shows what changed, Generate Migration writes the SQL and the rollback script and asks about renames, lint marks risky statements in the file, and Migrate... names the database before it runs. It is an early version (0.1.1), free, and open source under the Apache License 2.0.

Originally published at migrax.org.

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