如何在WHERE子句中将“ IN”与“ CASE语句”一起使用？

Question

Below is my MYSQL Query

select * from `ordermaster` where OrderStatus in (case when 1= 0 then OrderStatus else ("Completed","Cancelled") end)

as you can see 1st condition is ALL and next condition is Specific.

if condition 1 is satisfied then I would like to return entire data wrt orderstatus but if condition is satisfied then I want only records whose OrderStatus is "Completed" OR "Cancelled" but this is giving issue. I can directly use "IN" but cannot use with "CASE" statement.

Thanks, Rahul

Answer 1

SELECT ordermaster
    CASE 
        WHEN OrderStatus = 1 THEN 'Completed'
        WHEN OrderStatus = 0 THEN 'Cancelled'
    END AS STATUS 
FROM ordermaster;