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During the 15th century, the European countries of Spain and Portugal began sending ships on expeditions to find new trade routes to Asia. An accidental outcome of this search was the discovery by Christopher Columbus in of land in the Western Hemisphere. Although he and his immediate successors failed to recognize it, he had found another world: the Americas.
Join Stack Overflow to learn, share knowledge, and build your career. Connect and share knowledge within a single location that is structured and easy to search. I have a table with existing data. Is there a way to add a primary key without deleting and re-creating the table? Suppose you have a table named test1 , to which you want to add an auto-incrementing, primary-key id surrogate column.