How can I alter a primary key constraint using SQL syntax?
Solution 1:
Yes. The only way would be to drop the constraint with an Alter table then recreate it.
ALTER TABLE <Table_Name>
DROP CONSTRAINT <constraint_name>
ALTER TABLE <Table_Name>
ADD CONSTRAINT <constraint_name> PRIMARY KEY (<Column1>,<Column2>)
Solution 2:
PRIMARY KEY CONSTRAINT cannot be altered, you may only drop it and create again. For big datasets it can cause a long run time and thus - table inavailability.