This means you can't use <validCheckSum> to mitigate problems when migrating from one Liquibase version to another. For example:
- I apply a changeSet to the DB using Liquibase v1.0, and it generates a hash of X.
- I don't change the original changeSet, but I update to Liquibase v1.1. Now my changeSet has a hash of Y, and liquibase won't apply any further changeSets.
- I add <validCheckSum>Y</validCheckSum> to the changeSet to control this - telling Liquibase the hash in DATABASECHANGELOG is actually Y not X. I can continue my migration with Liquibase 1.1.
- Now I update to Liquibase 1.2. The hash of my original changeSet is recomputed as Z. I have to change my existing changeSet to <validCheckSum>Z</validCheckSum>.