Is Mysql IF EXIST what should be used for this query? -

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select social_members.*       , social_mcouple.*   m_id = '".$_session['userid'] . "'     , c_id = '".$_session['userid'] . "'

select fields social_members.* , if social_mcouple.c_id = $_session['userid'] select fields social_mcouple.* well. can done if exist , if how. thanks

if undertand correctly, outer join better here.

select social_members.*      , social_mcouple.*    social_members    left outer join social_mcouple      on social_members.m_id=social_mcouple.c_id   m_id='".$_session['userid']."'

this retrieve rows each member, , corresponding rows social_mcouple. if there no corresponding rows in social_mcouple table, social_mcouple.* rows in result null.

depending upon exact needs, , relationship between 2 tables, may better running 2 queries, 1 retrieve matching rows social_members, , other retrieve rows social_mcouple. whether take outer join or 2 separate queries depend upon "shape" of data want back.

and in case, thinking it's not possible return different number of columns depending upon data. (e.g. social_members columns if there no applicable social_mcouple rows.)


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