Changesets and updating work
Therefore, it is usually best to have just one change per change Set unless there is a group of non-auto-committing changes that you want applied as a transaction such as inserting data.
The type of a database which that change Set is to be used for.
If there was a valid reason for the change Set to have been changed and you want to ignore this error, update the databasechangelog table so that the row with the corresponding id/author/filepath has a null value for the check sum.
Each changeset has zero, one or two parent changesets.Check sums are also used in conjunction with the “run On Change” change Set attribute.There are times you may not want to add a new change Set because you only need to know about the current version, but you want this change applied whenever it is updated.The value of storing the check sum is so that Liquibase can know if someone changed the changes in the change Set since it was run.If the change Set was changed since it was run, Liquibase will exit the migration with an error because it cannot know what was changed and the database may be in a state different than what the change Log is expecting.