Hook provides a set of functions that allow for executing checks prior to executing migration statements.

Migration is a set of statements that will alter the database structure or or data.

CheckFunc is a function that checks the state of data in the database to determine if a migration will fail, and if so to report the data that is problematic so it can be fixed.

Migrations are a set of migrations by version.

Problems are reports of data issues that were identified by a CheckFunc.

RepairFunc is a function that alters data in the database to resolve issues that would prevent a migration from successfully running.

Repairs are reports of changes made to data by a RepairFunc.