MySQL Limiting a query to one consistent value
My current query returns a table like:
+------------+
value1 | ....
value1 | ....
value2 | ....
value3 | ....
+------------+
I want:
+------------+
value1 | ....
value1 | ....
+------------+
I want to only receive all rows with the first value. Normally I would do a WHERE clause if I knew that value, and I cannot use a LIMIT because e开发者_Python百科ach value has a different number of rows.
Right now My query looks like:
SELECT u.*, n.something, w.*
FROM ... AS u, ... AS n, ... AS w
WHERE u.id = n.id
AND w.val = n.val
AND u.desc LIKE '%GET REQUEST VARIABLE%'
This works great, except I get way too many rows and using PHP to do this ruins code portability and is superfluous.
Not sure but I think you might be able to get it with this:
SELECT u.*, n.something, w.*
FROM ... AS u
JOIN ... AS n ON u.id = n.id
JOIN ... AS w ON w.val = n.val
JOIN (
SELECT col
FROM ... AS u2
WHERE u2.desc LIKE ?
LIMIT 1
) AS u2 ON u2.col = u.col
where the ...
in the inner SELECT
is the same table aliased to u
before.
EDIT: One more thing: I assumed col
is different for different desc
values; if not, you would have to repeat the WHERE
in the outer SELECT
as well.
(If you're not familiar with prepared statements, ?
is where your '%...%'
would go... and don't forget to escape it against Bobby Tables; if you are, of course, the library will do it for you :) )
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