simplified version of my query
SELECT *
FROM logs
WHERE pw='correct' AND CASE WHEN id<800 THEN success=1 ELSE END
AND YEAR(timestamp)=2011
this doesn't work. What i'm trying to do is to add in success=1
only for rows with id<800
, else ignore this check.
how do i write this? thanks!
edit: to clarify, this what the table looks like
|id | pw | success |
--------------------------
|700 | correct | 1 |
|710 | correct | 1 |
|900 | correct | NULL |
|999 | correct | 0 |
I'm trying to return all the rows, the column pw
cannot be ignored.
You don't have to use CASE...WHEN, you could use an OR condition, like this:
WHERE
pw='correct'
AND (id>=800 OR success=1)
AND YEAR(timestamp)=2011
this means that if id<800, success has to be 1 for the condition to be evaluated as true. Otherwise, it will be true anyway.
It is less common, however you could still use CASE WHEN, like this:
WHERE
pw='correct'
AND CASE WHEN id<800 THEN success=1 ELSE TRUE END
AND YEAR(timestamp)=2011
this means: return success=1
(which can be TRUE or FALSE) in case id<800, or always return TRUE otherwise.
SELECT *
FROM logs
WHERE pw='correct'
AND CASE
WHEN id<800 THEN success=1
ELSE 1=1
END
AND YEAR(TIMESTAMP)=2011
This is working Oracle example but it should work in MySQL too.
You are missing smth - see IN after END Replace 'IN' with '=' sign for a single value.
SELECT empno, ename, job
FROM scott.emp
WHERE (CASE WHEN job = 'MANAGER' THEN '1'
WHEN job = 'CLERK' THEN '2'
ELSE '0' END) IN (1, 2)
You can transform logical implication A => B
to NOT A or B
. This is one of the most basic laws of logic. In your case it is something like this:
SELECT *
FROM logs
WHERE pw='correct' AND (id>=800 OR success=1)
AND YEAR(timestamp)=2011
I also transformed NOT id<800
to id>=800
, which is also pretty basic.
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