PreventLockingColumnOrIndex

Last updated: January 30, 2026

The PreventLockingColumnOrIndex custom policy check mandates that ADD COLUMN and ADD INDEX execute online, rather than locally. This prevents the database from locking specific objects while other database tasks are in progress.

This example utilizes MariaDB. You can use this check as it is or customize it further to fit your needs in your SQL database. All Regex Custom Policy Checks can only run against the changelog, not against the database.

Before you begin

Scope

Database

changelog

MariaDB

  • Liquibase 4.29.0+

  • Python 3.10.14+

  • Configure a valid Liquibase Pro license key

  • Create a Check Settings file

  • Ensure the Liquibase Checks extension is installed. In Liquibase 4.31.0+, it is already installed in the /liquibase/internal/lib directory, so no action is needed.

  • If the checks JAR is not installed, download liquibase-checks-<version>.jar and put it in the liquibase/lib directory.

  • Maven users only: Add this dependency to your pom.xml file: <dependency> <groupId>org.liquibase.ext</groupId> <artifactId>liquibase-checks</artifactId> <version>2.0.0</version> </dependency>

  • Java Development Kit 17+ (available for Open JDK and Oracle JDK)

  • Linux, macOS, or Windows operating system

Procedure

These steps describe how to create the Custom Policy Check. It does not exist by default in Liquibase Pro.

1

Run this command in the CLI:

liquibase checks customize --check-name=SqlUserDefinedPatternCheck
2

Give your check a short name for easy identification

Use up to 64 alpha-numeric characters only.

In this example we will use:
PreventLockingColumnOrIndex
3

Set the Severity to return a code of 0-4 when triggered.

These severity codes allow you to determine if the job moves forward or stops when this check triggers. Learn more here: Use Policy Checks in Automation: Severity and Exit Code options: 'INFO'=0, 'MINOR'=1, 'MAJOR'=2, 'CRITICAL'=3, 'BLOCKER'=4

4

Set the SEARCH_STRING to this valid regular expression:

Regular expression search string
(?is)(?=.*\b(alter\s*table|create)\b)(?=.*\b(column|index)\b)(?!.*\b(algorithm\s*=\s*inplace\s*,\s*lock\s*=\s*none)\b).*
5

Set the MESSAGE to display when a match for the regular expression <SEARCH_STRING> is found in a Changeset.

In this example we will use:
Adding a COLUMN or INDEX needs to be done in an online manner.
6

Set STRIP_COMMENTS to true if you want to remove the comments from the output.

The regex custom policy check is created successfully.

Sample Failing Scripts

ALTER TABLE new_table_01 ADD COLUMN A VARCHAR(45) NULL DEFAULT NULL AFTER name;

ALTER TABLE new_table_01 ADD INDEX b_index (b);

CREATE INDEX b_index ON new_table_01 (b);

Sample Passing Scripts

ALTER TABLE new_table_01 ADD COLUMN A VARCHAR(45) NULL DEFAULT NULL AFTER name, algorithm = inplace, lock=none;

ALTER TABLE new_table_01 ADD INDEX b_index (b), algorithm = inplace, lock=none;

CREATE INDEX b_index ON new_table_01 (b), algorithm = inplace, lock=none;

Sample Error Message

CHANGELOG CHECKS ---------------- Checks completed validation of the changelog and found the following issues: Check Name:         Check for specific patterns in sql (CannotModifyUsersOrRoles) Changeset ID:       01 Changeset Filepath: sql/main/100_ddl/97_add_column.sql Check Severity:     MINOR (Return code: 1) Message:            Adding a COLUMN or INDEX needs to be done in an online manner.