Reputation: 25
I have these two tables:
CREATE TABLE
tbl_member
(
ID
int(11) NOT NULL AUTO_INCREMENT,
MemberNo
varchar(30) DEFAULT '',
Surname
varchar(40) DEFAULT NULL,
GivenNames
varchar(30) DEFAULT NULL,
PRIMARY KEY (ID
),
);
CREATE TABLE
tbl_sale
(
ID
int(11) NOT NULL AUTO_INCREMENT,
TxnType
smallint(2) NOT NULL,
SalesID
varchar(20) NOT NULL,
Reference
int(11) NOT NULL,
TxnDate
datetime NOT NULL,
MemberID
int(11) DEFAULT NULL,
PRIMARY KEY (ID
),
KEY MemberIDX
(MemberID
),
KEY TxnDateIDX
(TxnDate
)
);
But whenever I try to add this
ALTER TABLE tbl_sale ADD CONSTRAINT tbl_sale_fk1 FOREIGN KEY (
MemberID
) REFERENCES tbl_member
(ID
);
I am getting this error
Error Code: 1215. Cannot add foreign key constraint
I don't understand why I am getting this error, Any help is appreciate
Thanks
Upvotes: 0
Views: 126
Reputation: 1069
You are not allowed to have MemberID int(11) DEFAULT NULL
. It must be NOT NULL
.
Upvotes: 0