MySQL multiple group by using -


now using query : 

select * messages receiverid='$uid' or senderid='$uid' group recei verid,senderid order datex desc

but results

id  receiverid  senderid  1      2            1  2      1            2

but want showing 1 result syntax. example:

id  receiverid  senderid  1      2            1

or 

id  receiverid  senderid  2      1            2

you want use least() , greatest():

select * messages receiverid='$uid' or senderid='$uid' group least(receiverid, senderid), greatest(receiverid, senderid) order datex desc;

however, should list columns explicitly in select. using mysql extension have columns in select not in group by. bad idea unless understand doing.


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