Can someone help me in below query I always get x.salesChannel as Unknown column
SELECT Column1,
Column2,
(
SELECT CASE
WHEN `cr`.`CRColumn` is not null
AND `cr`.`CRColumn` <= `ca`.`caColumn` THEN `cr`.`CRColumn`
WHEN `cr`.`CRColumn` is not null
AND `cr`.`CRColumn` > `ca`.`caColumn` THEN `cr`.`CRColumn`
WHEN `cr`.`CRColumn` is not null
AND `cr`.`CRColumn` is null THEN `cr`.`CRColumn`
END as salesChannel
FROM `table1` `ca`
LEFT JOIN `Table2` `bc` ON `bc`.`contract_action_id` = `contract`.`id`
LEFT JOIN `Table3` `cr` ON `cr`.`pnr` = `bc`.`pnr`
) AS `x`
FROM `table1` `contract`
WHERE `contract`.`type` = ?
AND x.salesChannel IS NOT NULL
AND x.salesChannel IN (?, ?)