PreparedStatement,using one parameter for multiple “?”

Question

I have a insert if not exists query as below.

BEGIN
    IF NOT EXISTS (SELECT * FROM tbl_sampleTable WHERE name = ? or subject = ?)
    BEGIN
        INSERT INTO         


        

Answer 1

Just in this case you might use SQL variables. It is not a general solution. And also many SQL vendor specific variants know such insert-when-not-exists constructs, not needing such archaic code.

BEGIN
    DECLARE @MyName varchar(100);
    DECLARE @MySubject varchar(100);
    SET @MyName = ?;
    SET @MySubject = ?;
    IF NOT EXISTS (SELECT * FROM tbl_sampleTable WHERE name = @MyName OR subject = @MySubject)
    BEGIN
        INSERT INTO tbl_sampleTable(subject, name) VALUES (@MySubject, @MyName)
    END
END