Understanding Rollback

General Discussion
1

Hi,
    I’m not sure that I fully understand how the rollback feature is supposed to work.
Given a simple change log like:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>


       
           
               
           
       



If I run:

sh ./liquibase <br>  --defaultsFile=mydb.properties <br>  --changeLogFile=testlog.xml <br> 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.

2

(Missed your question originally, sorry)


The tag is created via the “liquibase tag” command, and is not connected to the ids at all.


Nathan

3

Can give a example of rollback with rollback,on command, 

thanks

4

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

Datical, Inc. http://www.datical.com/

5

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.    

6

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.

Nathan