Reputation: 1333
I want to implement ternary conditional operator in MySQL. I have a table in which one field id exist. Its value may be null. I want to display id
in ternary conditional format like this:
select id = id == null ? 0 : id;
Is it possible in MySQL?
Upvotes: 120
Views: 64737
Reputation: 385274
The documentation is your friend; you should read it!
It says:
IFNULL(expr1,expr2)
If
expr1
is notNULL
,IFNULL()
returnsexpr1
; otherwise it returnsexpr2
.
And then lots of examples. This is equivalent to using a ternary conditional with a comparison to NULL
and the comparison subject as the second operand; that it doesn't happen to use the symbols ?
and :
to get you there is not really relevant to anything.
So, in your case:
SELECT IFNULL(`id`, 0) FROM `table`
If you're desperate to provide three operands explicitly (why?!), then switch to IF
:
SELECT IF(`id` IS NULL, 0, `id`) FROM `table`
Upvotes: 62
Reputation: 37009
There are two ways that you can implement the same logic as a ternary operator:
IF
function, eg. IF(expression, true result, false result)
Use the CASE
expression, eg.
CASE WHEN expression THEN <true result> ELSE <false_result> END
When you are checking for NULL then you can use the IFNULL
or COALESCE
functions, eg.
IFNULL(ID, 0)
COALESCE(ID, 0)
Upvotes: 28