DB data migration and schema consistency

[Dmytro Vitel]

We need scripts to migrate quiz data from one DB to another looking onto the:

0. Part of schema which should be migrated from the source.
1. Schema consistency checks between source and target. Fail on schema miss or thinks about default values!
2. New unique ids of entities created in the target.
3. Should we have manual scripts in some cases to populate data in the new target schema? How it is better to integrate them?

[Dmytro Vitel]

Added initial scripts to check source and target schema for quiz tables.
Interface is: we provide quiz_id and target instructor_id and data is migrated for that quiz and instructor.
Schema is separated onto required one and varied. Ids belongs to required schema, same with author_id

[Dmytro Vitel]

• Migrate the user, the author of the script, and all of their quizzes
• Write tests to cover scenarios of schema incompatibility