how to declare variable in mysql and set its value to the count result

Question

I'd like to declare an int variable perform a count query and set the result to that variable, but mysql doesnt recognize the declared variable I've already tried this:

DECLARE itExists INT DEFAULT 0;
SELECT COUNT(*) FROM grades WHERE statId = 1 INTO itExists;
SELECT itExists AS cnt;

it always says:

Query: DECLARE itExists INT DEFAULT 0

Error Code: 1064
You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'DECLARE itExists INT DEFAULT 0' at line 1

Execution Time : 0 sec
Transfer Time  : 0 sec
Total Time     : 0 sec
--------------------------------------------------

Query:  select count(*) from grades WHERE statId = 1 into itExists

Error Code: 1327
Undeclared variable: itExists

Possible duplicate of [How to declare a variable in MySQL?](https://stackoverflow.com/questions/11754781/how-to-declare-a-variable-in-mysql) — P.Salmon, Nov 01 '19 at 14:41

score 0 · Accepted Answer · answered Nov 01 '19 at 14:40

0

You have to use session variables

SELECT COUNT(*) FROM grades WHERE statId = 1 INTO @itExists;
SELECT @itExists AS cnt;

answered Nov 01 '19 at 14:40

nbk

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how to declare variable in mysql and set its value to the count result

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