For Higher Computing Science, revise the use of primary and foreign keys and the difference between flat file and relational databases.

Can you do a foreign key within a single table, though? I've only ever seen foreign key constraints tying a field in one table to a field in another table.

Foreign key 'geneassay_fk' references invalid column 'geneassay' in referencing table 'b_SequencingData_seq'. Msg 1750, Level 16, State 0, Line 43 Could not create constraint.