runOnChange changeset attribute

The runOnChange attribute executes the change the first time it is seen and each time the changeset is modified.

Liquibase determines that a changeset has been modified by comparing the MD5 checksum for the changeset to the checksum stored in the DATABASECHANGELOG table. If the runOnChange attribute is not set or set to false, Liquibase will generate a checksum error if a changeset is modified after it has been deployed to a database. This is done to notify you that a changeset has been unexpectedly modified.

Uses

The runOnChange attribute is useful for changesets that you would like to run each time they are modified. Common examples are Views and Stored Procedures that use the CREATE OR REPLACE logic. If you copy the entire text of the stored procedure to a new changeset each time you make a change, you will not only end up with a very long changelog, but you will lose the merging and diff-ing power of your source control. Instead, put the text of the Stored Procedure in a changeset with a runOnChange=”true” attribute. The stored procedure will be recreated only when there is a change to the text.

Using runOnChange

The default value for runOnChange is false. Set runOnChange to true for changesets that should be executed whenever they are modified.

XML example

<changeSet  author="your.name"  id="changeset01" runOnChange="true" >
        <createProcedure>
        . . .
        </createProcedure>
</changeSet>

SQL example

--changeset your.name:changeset1 runOnChange:true
CREATE or REPLACE . . .

YAML example

changeset:
      id: changeset1
      author: your.name
      runOnChange: true
      changes:
      . . .

JSON example

{ "changeSet" :
        {"id": changeset1,
        "author": your.name,
        "runOnChange": true,
        "changes":
          [
           . . .
          ]
        }
 }