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Question

I am very confused as to why this isn't executing the second else if statement. I just need the statement to run when there is no First_name and Surname provided, but has Age. It runs the first if statement, but not the second part.

Here is the code

ALTER PROCEDURE [PEOPLE]
(
    @AGE int,
    @SURNAME nvarchar(10),
    @FIRST_NAME nvarchar(10)
)
AS
BEGIN   
    IF(@SURNAME IS NOT NULL AND @FIRST_NAME IS NOT NULL)
        BEGIN
            SELECT * 
            FROM MEMBERS
            WHERE Is_Active = 1
            AND (FIRST_NAME = @FIRST_NAME AND SURNAME=@SURNAME)
        END     
        
        -- This else statement isn't being executed :-(
        ELSE IF(@AGE <> -1 AND @FIRST_NAME='' AND @SURNAME='')
            BEGIN
                SELECT *
                FROM MEMBERS
                WHERE(AGE = @AGE)
            END         
    END

Here is how I'm executing it:

exec [PEOPLE] @AGE=24, @FIRST_NAME='', @SURNAME=''

I would be grateful if someone could help. Thanks

Answer 1

The ELSE IF , as it is, requires that both @FIRST_NAME and @SURNAME not be null, which is already satisfied in the IF .

You may need to rewrite the ELSE IF like this:

 ELSE IF(@AGE <> -1 AND (@FIRST_NAME IS NULL OR @FIRST_NAME='') AND (@SURNAME IS NULL OR @SURNAME=''))

Answer 2

Try this one:

ALTER PROCEDURE [PEOPLE]
(
    @AGE int,
    @SURNAME nvarchar(10),
    @FIRST_NAME nvarchar(10)
)
AS
BEGIN   
  SELECT * 
  FROM MEMBERS
  WHERE
    (
       (IsNull(@FIRST_NAME, '') <> '') AND
       (IsNull(@SURNAME, '') <> '') AND
        FIRST_NAME = IsNull(@FIRST_NAME, '') AND
        SURNAME = IsNull(@SURNAME, '') AND
        Is_Active = 1
    )
    OR
    (
      @AGE <> -1 AND
      (IsNull(@FIRST_NAME, '') = '') AND
      (IsNull(@SURNAME, '') = '') AND
      (AGE = @AGE)
    )
END