ALTER TABLE <table name> DROP CONSTRAINT <primary key name>
ALTER TABLE <table name> ALTER COLUMN <column name> <new data types>
ALTER TABLE <table name> ADD CONSTRAINT <primary key name> PRIMARY KEY (<columns for the primary key>)
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability