Every fault made when designing a Database through SQL gets recovered in many cases, but when the field is assigned as primary kay I wonder that Alter Table thetable drop thefield will make your DBMS cry 'Yoh man that's a primary key go play with foggs !' the best practice in such is that the primary key is a filed that have a constraint dropping the constraint wil make you DBMS obey you as a master : 'ALTER TABLE thetable DROP CONSTRAINT thekey'. In most DBMS this woks fine and about yours, I have doubts, just try and never get tired !
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