Question

SELECT COUNT(*) as totalHappenings FROM `happenings` WHERE `userId` = ? 
UNION 
SELECT COUNT(*) as xHappenings FROM `happenings` WHERE `userId` = ? AND `destinationObjectType` = \'2\' 
UNION 
SELECT COUNT(*) as yHappenings FROM `happenings` WHERE `userId` = ? AND `destinationObjectType` = \'1\'

Since it’s the same table, and I don’t wanna pass through 3 times the userId parameter how can I solve this the best way?

Answer 1

SELECT 
    COUNT(*) AS totalHappenings,
    SUM(CASE WHEN `destinationObjectType` = \'2\' THEN 1 ELSE 0 END) AS xHappenings, 
    SUM(CASE WHEN `destinationObjectType` = \'1\' THEN 1 ELSE 0 END) AS yHappenings 
FROM `happendings` 
WHERE `userId` = ?

Result:

totalHappenings xHappenings yHappenings
      24            10          14