MySQL if语句选择多行

Question

I need to retrieve a set of data if a condition is true, and a set of other ata if the condition is false.

I searched in mysql manual and I tested the select case when statement, but as my subqueries return multiple rows, I'm not able to use it.

Is it a simple way to write a query with if statement? (without using stored procedure)

Here is my condition:

select case when ( right(from_unixtime(300 * floor(unix_timestamp(now())/300)) - INTERVAL 10 MINUTE, 8) = '23:50:00' ) then ( select SERVER_KEY from OVERSERVER ) else ( select SERVER_KEY from SERVER  ) end;

Thanks

Answer 1

try something like this:

select SERVER_KEY from OVERSERVER
where right(from_unixtime(300 * floor(unix_timestamp(now())/300)) - INTERVAL 10 MINUTE, 8) = '23:50:00'
union all
select SERVER_KEY from SERVER
where right(from_unixtime(300 * floor(unix_timestamp(now())/300)) - INTERVAL 10 MINUTE, 8) != '23:50:00'

Answer 2

I am not sure but just give a try this-

select SERVER_KEY from (case when ( right(from_unixtime(300 * floor(unix_timestamp(now())/300)) - INTERVAL 10 MINUTE, 8) = '23:50:00' ) then "OVERSERVER" else "SERVER"

OR

select SERVER_KEY from (case when ( right(from_unixtime(300 * floor(unix_timestamp(now())/300)) - INTERVAL 10 MINUTE, 8) = '23:50:00' ) then OVERSERVER else SERVER

Note: above query is not tested.