Which of the following is the valid syntax for adding a PRIMARY KEY constraint to an existing table? ( refer to the tables in the JustLee Books database). a. ALTER TABLE tablename ADD CONSTRAINT PRIMARY KEY (columnname); b. ALTER TABLE tablename ADD CONSTRAINT (columnname) PRIMARY KEY constraintname; c. ALTER TABLE tablename ADD [CONSTRAINT constraintname] PRIMARY KEY; d. None of the above is valid syntax.

Which of the following is the valid syntax for adding a PRIMARY KEY constraint to an existing table? ( refer to the tables in the JustLee Books database). a. ALTER TABLE tablename ADD CONSTRAINT PRIMARY KEY (columnname); b. ALTER TABLE tablename ADD CONSTRAINT (columnname) PRIMARY KEY constraintname; c. ALTER TABLE tablename ADD [CONSTRAINT constraintname] PRIMARY KEY; d. None of the above is valid syntax.

Oracle 12c: SQL

3rd Edition

ISBN:9781305251038

Author:Joan Casteel

Publisher:Joan Casteel

Chapter4: Constraints

Section: Chapter Questions

Problem 20MC: Which of the following is the valid syntax for adding a PRIMARY KEY constraint to an existing...

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