Liquibase and JPA annotated entities

Question

I am trying to use Liquibase together with JPA annotations, but I does not seem to work.

I've got a clean DB with no tables and one JPA entity in my project. When I run liquibase diff, it claims, that DB is up-to-date - but it is simply not true.

maven config for liquibase plugin:

  <plugins>
        <plugin>
            <groupId>org.liquibase</groupId>
            <artifactId>liquibase-maven-plugin</artifactId>
            <version>3.3.1</version>
            <configuration>
                <changeLogFile>src/main/resources/liquibase/changelog.xml</changeLogFile>
                <referenceUrl>hibernate:spring:com.mycompany.entity?dialect=org.hibernate.dialect.PostgreSQLDialect</referenceUrl>
                <driver>org.postgresql.Driver</driver>
                <url>jdbc:postgresql://localhost:5432/liqubase-test</url>
                <username>postgres</username>
                <password>postgres</password>
            </configuration>
            <executions>
                <execution>
                    <phase>process-resources</phase>
                    <goals>
                        <goal>update</goal>
                    </goals>
                </execution>
            </executions>
            <dependencies>

                <dependency>
                    <groupId>org.liquibase.ext</groupId>
                    <artifactId>liquibase-hibernate4</artifactId>
                    <version>3.4</version>
                </dependency>

                <dependency>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-beans</artifactId>
                    <version>4.1.4.RELEASE</version>
                </dependency>

            </dependencies>
        </plugin>
    </plugins>

changelog.xml file:

<?xml version="1.0" encoding="UTF-8"?>

<databaseChangeLog
        xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
         http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.0.xsd">



</databaseChangeLog>

and when I run generateChangeLog task:

[INFO] Scanning for projects...
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building liqubase-sample 1.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- liquibase-maven-plugin:3.3.1:generateChangeLog (default-cli) @ liqubase-sample ---
[INFO] ------------------------------------------------------------------------
[INFO] Executing on Database: jdbc:postgresql://localhost:5432/liqubase-test
[INFO] Generating Change Log from database postgres @ jdbc:postgresql://localhost:5432/liqubase-test (Default Schema: public)
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<databaseChangeLog xmlns="http://www.liquibase.org/xml/ns/dbchangelog" xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.3.xsd http://www.liquibase.org/xml/ns/dbchangelog-ext http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd"/>
[INFO] Output written to Change Log file, null
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.213 s
[INFO] Finished at: 2015-01-10T14:47:24+01:00
[INFO] Final Memory: 9M/216M
[INFO] ------------------------------------------------------------------------

Answer 1

Liquibase is correctly comparing the target database schema against the changelog you've specified.... which is empty :-)

You need to do some extra work. The following article appears to do a good job in outlining a workflow for liquibase with Hibernate:

• http://www.operatornew.com/2012/11/automatic-db-migration-for-java-web.html

It appears overly complicated, but what liquibase is doing is capturing all changes to the schema. In a nutshell you need to bring you DB to the latest captured state, generate the delta and then add this delta into your source code.

I hope this helps.