如何在WHERE子句中使用IF ELSE

Question

是否可以在WHERE子句中使用IF ELSE ...

WHERE transactionId like @transactionId
AND transactionType like @transactionType
AND customerId like @customerId
IF(@transactionType='1')
AND qTable.statusId like 'SIGNED'
ELSE
AND rTable.statusId like 'ACTIVE'

Answer 1

您不能在IF ELSE子句中使用WHERE语句。请改用CASE：

WHERE transactionId like @transactionId
AND transactionType like @transactionType
AND customerId like @customerId
AND CASE WHEN @transactionType = '1' THEN qTable.statusId like 'SIGNED' 
    ELSE rTable.statusId like 'ACTIVE' END

Answer 2

WHERE transactionId like @transactionId
AND transactionType like @transactionType
AND customerId like @customerId
AND 
  ((@transactionType='1' AND qTable.statusId like 'SIGNED')
OR 
  (@transactionType <> '1' AND like 'ACTIVE') )

Answer 3

这是你需要的吗？

WHERE transactionId like @transactionId
AND transactionType like @transactionType
AND customerId like @customerId
AND ((transactionType='1' and qTable.statusId like 'SIGNED') or (transactionType <> '1' and rTable.statusId like 'ACTIVE'))