Installer: Running Your First Update
The main Liquibase command you will use is
update, which applies any unrun changes in your changelog to your database.
Step One: Run
To run your first update:
- Open a command-line or Terminal app.
- Navigate to your
...examples/sql directory(or xml).
- In your command prompt run
You should see a message saying
Update has been successful.
Step Two: Check your Developer Console Page
Next, refresh your developer database console page.
You should now see the following tables added to the object view:
liquibase update, your database now matches the desired database state as defined by the changelog script.
The DATABASECHANGELOG and DATABASECHANGELOGLOCK tables are Liquibase-metadata tables, the COMPANY and PERSON tables were created by the changelog.
Step Three: Open your changelog File
Now, open the
com/example/sample.changelog.sql file in your favorite text editor.
In each file you can see how changes were defined as a series of changesets. Each changeset is uniquely identified by the
author fields. Liquibase uses these fields to track what changes have been run and what has not.
When you ran the
update command, Liquibase evaluated which changesets had not been run against your target database, then ran them.
Step Four: Add New changesets
Running the update command allowed your developer database to match the defined state. Now that they match, you can start adding additional changes you need.
If you have not run your first update, please follow the instructions in the previous sections before completing this section.
In this example, we will add a new changesets to create a
works for column in the PERSONS table.
To add this changeset, open the sample changelog file in your existing editor, and one of the following to then END of the file:
XML changelog example code
SQL changelog example code
Note: It's best practice to wrap every statement in its own changeset block.
liquibase update again & refresh your database console. You will see the new column on the PERSON table.
Step Five: Promoting Changes
Now that we added a new changeset and the database structure is what we want, we are ready to apply those changes to our integration database.
At this time in the workflow, you should commit your changelog to version control and/or build an artifact containing it, however, for this tutorial we will run it directly against our other database.
To apply the changes to the integration database run:
liquibase --url=jdbc:h2:tcp://localhost:9090/mem:integration update
By passing along the
--url parameter, you override the url value specified in the
liquibase.properties file, but still use all the other parameters in the file.
After running update against the integration database, you should now see the COMPANY and PERSON tables in your integration web console.