Well i am new to yii framework i need to execute subquery like below-
(select concat(cp.id,'|',campp.prosjektkode,'|',cp.kunder_id)
from campaign_company cp
left join campaign campp
on cp.campaign_id= campaign.id
where cp.id<c1.id limit 1) as prev
problem is yii2 is looking for column with name of '|' and error given like -
SQLSTATE[42703]: Undefined column: 7 ERROR: column "|" does not exist
suggest me what to right here...
Thanks in advance