mysql function if/else - mysql

Question

I have a function that returns a date string. I need this because I can't use a variable in a view, but I can use a function that returns a variable that I set ahead of time...
So I got all that working, but then I decided that if that I wanted it to return the current date if no date variable was set. I thought the code below wold work, but I get syntax errors...
DELIMITER $$
USE `cc`$$
DROP FUNCTION IF EXISTS `ox_date`$$
CREATE FUNCTION `ox_date`() RETURNS CHAR(50) CHARSET latin1
DECLARE ox VARCHAR(20)
IF #oxdate <1 THEN SET ox = CURDATE$$
ELSE SET ox = #oxdate$$
RETURN ox $$
DELIMITER ;
I tried isnull on that first if, but it wasn't any help.

Answer 1

I'm no expert but here are a few of things I see.
First, you've got
DELIMITER $$
and then use it in the function itself. That DELIMITER line allows you to use the semicolons within the body of the function. Otherwise the ';' would end the CREATE FUNCTION statement prematurely.
Also, the line
DECLARE ox varchar(20)
is missing a semicolon at the end.
And then you're missing the
END IF;
after the else condition.
Also what about the BEGIN END$$ wrapped around the function's definition?
I'd expect a stored function to generally take the form:
DELIMITER $$
DROP FUNCTION IF EXISTS `testdb`.MyFunc$$
CREATE FUNCTION `testdb`.`MyFunc` () RETURNS INT
BEGIN
DECLARE someVar varchar(20);
# some stuff
RETURN something;
END $$
DELIMITER ;
Modifying the guts of the function to suit your needs and setting the return type as appropriate.
Anyway, I'm not an expert but that is what I see and hope that helps.

Answer 2

Why do you need to fiddle with the delimiter? For simple logic prefer the IF function to the IF statement.
CREATE FUNCTION `ox_date`( )
RETURNS CHAR(50) CHARSET latin1
RETURN IF(#oxdate < 1 OR #oxdate IS NULL, CURDATE(),#oxdate)
Else
DELIMITER $$
USE `cc`$$
DROP FUNCTION IF EXISTS `ox_date`$$
CREATE FUNCTION `ox_date`( )
RETURNS CHAR(50) CHARSET latin1
RETURN IF(#oxdate < 1 OR #oxdate IS NULL, CURDATE(),#oxdate)$$
DELIMITER ;