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Add a Change Type


Implementing Liquibase extensions requires an understanding of Java. You will be creating classes, overriding methods, and working with inheritance hierarchies.

Project Setup

If you have not already created a repository to hold your code, see Your First Extension in the Getting Started guide.


When adding support for a new change type, the interface you are going to implement is liquibase.change.Change.

Change implementations do not need to be thread-safe. ChangeFactory will generate a new instance of them each time they are used.


There is a liquibase.change.AbstractChange base class you can use which limits the number of methods you must implement.

API Documentation

A complete description of the API, including what methods must be implemented and how is available on the liquibase.change.Change API page.

Example Code

package com.example.change;

import liquibase.change.AbstractChange;
import liquibase.change.ChangeMetaData;
import liquibase.change.DatabaseChange;
import liquibase.database.Database;
import liquibase.statement.SqlStatement;
import liquibase.statement.core.UpdateStatement;

        name = "setPassword",
        description = "Sets a user's password",
        priority = ChangeMetaData.PRIORITY_DEFAULT
public class SetPasswordChange extends AbstractChange {
    private String username;
    private String password;

    public SqlStatement[] generateStatements(Database database) {
        return new SqlStatement[]{
                new UpdateStatement(null, null, "app_users")
                        .addNewColumnValue("password", password)
                        .setWhereClause("username='" + database.escapeStringForDatabase(username) + "'")

    public String getConfirmationMessage() {
        return "Password has been changed for " + username;

    public String getUsername() {
        return username;

    public void setUsername(String username) {
        this.username = username;

    public String getPassword() {
        return password;

    public void setPassword(String password) {
        this.password = password;