[TYPO3-dev] Performance of FIND_IN_SET in JOIN condition

[Marc Bastian Heinrichs]

Hey,

does anybody have an information about the performance (or could test it
in a huge setup) of the following query

SELECT fe_users.* FROM fe_users LEFT JOIN fe_groups ON (
    fe_users.usergroup LIKE CONCAT ('%', fe_groups.uid, '%')
    OR fe_users.usergroup LIKE CONCAT ('%', fe_groups.uid)
    OR fe_users.usergroup LIKE CONCAT ('%', fe_groups.uid)
    OR fe_users.usergroup = fe_groups.uid
) WHERE fe_groups.uid IN(...)

in comparision to the following

SELECT fe_users.* FROM fe_users LEFT JOIN fe_groups ON
(FIND_IN_SET(fe_groups.uid, fe_users.usergroup)) WHERE fe_groups.uid IN(...)


Thanks in advance!


Regards
Marc Bastian