I have a problem. I want to use subquery tm
in LEFT JOIN .. ON
SELECT t.*,
(SELECT `uid` FROM `truck_transport` tm WHERE tm.from = t.station ORDER BY RAND() LIMIT 1) as tm
FROM `truck_trailer` t
LEFT JOIN `truck_transport` tm2 ON (tm2.uid = tm) ...
If I use subquery in FROM
result of rand is always the same.
Sorry for my language :/
try this
SELECT t.*, tm.uid
FROM `truck_trailer` t
LEFT JOIN (SELECT `uid` FROM `truck_transport` ORDER BY RAND() LIMIT 1) as tm
ON (tm.uid = t.station)
mynawaz has written a correct query.
Your subquery will always return only one result because of limit 1
. If you want only one result to come then use JOIN
instead of LEFT JOIN
. because left join table always returns matching rows and non matching with NULL
of right side table.
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