# Understanding Rollback **URL:** \ **Category:** General Discussion\ **Created:** [April 26, 2011, 11:07pm UTC](https://forum.liquibase.org/t/understanding-rollback/1245 "2011-04-26T23:07:00Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![tortoise\_74](https://avatars.discourse-cdn.com/v4/letter/t/5f8ce5/32.png) [@tortoise\_74](https://forum.liquibase.org/u/tortoise_74)\ **Post date:** [April 26, 2011, 11:07pm UTC](https://forum.liquibase.org/t/understanding-rollback/1245/1 "2011-04-26T23:07:00Z")
Hi,     I’m not sure that I fully understand how the rollback feature is supposed to work. Given a simple change log like: \                                                         If I run: sh ./liquibase \  --defaultsFile=mydb.properties \  --changeLogFile=testlog.xml \ rollbackSQL testlog I get an error (I get the same error using just rollbackSQL): Liquibase Home: /home/brucea/liquibase INFO 4/26/11 5:00 PM:liquibase: Successfully acquired change log lock INFO 4/26/11 5:00 PM:liquibase: Reading from DATABASECHANGELOG INFO 4/26/11 5:00 PM:liquibase: Successfully released change log lock Liquibase Update Failed: Could not find tag ‘testlog’ in the database SEVERE 4/26/11 5:00 PM:liquibase: Could not find tag ‘testlog’ in the database liquibase.exception.RollbackFailedException: Could not find tag ‘testlog’ in the database         at liquibase.changelog.filter.AfterTagChangeSetFilter.(AfterTagChangeSetFilter.java:28)         at liquibase.Liquibase.rollback(Liquibase.java:292)         at liquibase.Liquibase.rollback(Liquibase.java:268)         at liquibase.integration.commandline.Main.doMigration(Main.java:716)         at liquibase.integration.commandline.Main.main(Main.java:116) The changelog id “testlog” is clearly there in the DATABASECHANGELOG table. I am also unclear why I should not to provide a rollback tag at all. The implication is that a rollback tag is not the same thing as a changeset id. So what is it? Regards, Bruce. ---
**Author:** ![nvoxland](https://avatars.discourse-cdn.com/v4/letter/n/87869e/32.png) [@nvoxland](https://forum.liquibase.org/u/nvoxland)\ **Post date:** [April 26, 2011, 11:07pm UTC](https://forum.liquibase.org/t/understanding-rollback/1245/2 "2011-04-26T23:07:00Z")
(Missed your question originally, sorry) The tag is created via the “liquibase tag” command, and is not connected to the ids at all. Nathan ---
**Author:** ![un1405070192687r6id](https://avatars.discourse-cdn.com/v4/letter/u/9de053/32.png) [@un1405070192687r6id](https://forum.liquibase.org/u/un1405070192687r6id)\ **Post date:** [April 26, 2011, 11:07pm UTC](https://forum.liquibase.org/t/understanding-rollback/1245/3 "2011-04-26T23:07:00Z")
Can give a example of rollback with rollback,on command,  thanks ---
**Author:** ![un1382561729492r88id](https://avatars.discourse-cdn.com/v4/letter/u/c4cdca/32.png) [@un1382561729492r88id](https://forum.liquibase.org/u/un1382561729492r88id)\ **Post date:** [April 26, 2011, 11:07pm UTC](https://forum.liquibase.org/t/understanding-rollback/1245/4 "2011-04-26T23:07:00Z")
Here are a few resources: The Liquibase docs on rollback have a bit about what the rollback command means when you rollback using a tag: [http://www.liquibase.org/documentation/rollback.html](http://www.liquibase.org/documentation/rollback.html) > ## Datical, Inc. [http://www.datical.com/](http://www.datical.com/) ---
**Author:** ![un1405070192687r6id](https://avatars.discourse-cdn.com/v4/letter/u/9de053/32.png) [@un1405070192687r6id](https://forum.liquibase.org/u/un1405070192687r6id)\ **Post date:** [April 26, 2011, 11:07pm UTC](https://forum.liquibase.org/t/understanding-rollback/1245/5 "2011-04-26T23:07:00Z")
thank you very much! I think I have got it,I should define a tagDatabase. By the way, and is there a completed document of changeSet file? include insert,rollback,tagDatabase and so on.     ---
**Author:** ![nvoxland](https://avatars.discourse-cdn.com/v4/letter/n/87869e/32.png) [@nvoxland](https://forum.liquibase.org/u/nvoxland)\ **Post date:** [April 26, 2011, 11:07pm UTC](https://forum.liquibase.org/t/understanding-rollback/1245/6 "2011-04-26T23:07:00Z")
[http://www.liquibase.org/documentation/rollback.html](http://www.liquibase.org/documentation/rollback.html) gives some examples.  Tagging the database is usually done outside the changelog, like how you do a tag in git/svn/whatever.  If you want to automatically tag, tagDatabase is documented here: [http://www.liquibase.org/documentation/changes/tag\_database.html.](http://www.liquibase.org/documentation/changes/tag_database.html.) Nathan