Beginning SQL

Chapter 4
146
Remember, IBM DB2 doesn’t support adding NOT NULL after the table has been created, so you have to
go the long-winded route of copying the data to a temporary table, dropping the MemberDetails table,
and then re-creating it with the NOT NULL constraint, as shown in the following code:
CREATE TABLE TempMemberDetails
(
MemberId integer,
FirstName vargraphic(50),
LastName vargraphic(50),
DateOfBirth date,
Street varchar(100),
City varchar(75),
State varchar(75),
ZipCode varchar(12),
Email varchar(200),
DateOfJoining date
);
INSERT INTO TempMemberDetails
SELECT * FROM MemberDetails;
DROP TABLE MemberDetails;
CREATE TABLE MemberDetails
(
MemberId integer NOT NULL,
FirstName vargraphic(50),
LastName vargraphic(50),
DateOfBirth date,
Street varchar(100),
City varchar(75),
State varchar(75),
ZipCode varchar(12),
Email varchar(200),
DateOfJoining date
);
INSERT INTO MemberDetails
SELECT * FROM TempMemberDetails;
DROP TABLE TempMemberDetails;
Having added the NOT NULL constraint, via whichever means your database system requires, now execute
the following code, which adds the actual PRIMARY KEY:
ALTER TABLE MemberDetails
ADD CONSTRAINT memberdetails_pk PRIMARY KEY (MemberId);