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Deepak Rohan Sekar
Deepak Rohan Sekar
9,634 Points

Add foreign key and constraints Databases

I have to add a foreign key with constraint and reference, I think the piece of code below looks fine but it doesn't work.

1 Answer

Steven Parker
Steven Parker
229,920 Points

I don't see any code, but just in general, the syntax to add a foreign key constraint to an existing column is:

ALTER TABLE table_name ADD CONSTRAINT constraint_name
  FOREIGN KEY (column_name) REFERENCES other_table(other_column);