can someone please tell me the definition of data validations tasks. I am thinking this involves checking if the data being inputted is clean (i.e no duplicates, data types are accurately identified primary & foreign keys are in place e.t.c) my thinking is that to ensure this, you would use constraints that you stated during creation of the database.
also my 2nd question..where does these data validation tasks come in when migrating to a new database or trying to move data between two different systems.