so if the original SQL statement is:

SELECT junk.name, st.site_type, junk.location, junk.mapref
FROM junksite junk, site_type st
WHERE junk.site_type_id = st.id

the arrays would map as follows

name      -> 0<br>
site_type -> 1<br>
location  -> 2<br>
mapref    -> 3<br>
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so from there you can write

$array_ref = $sth->fetchall_arrayref( [0, 2] );
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