If you only want to find the rows that match apple, then just fetch the rows for apples: 

#untested

my $matrix_ref = $dbh->selectall_arrayref('
   SELECT some_col
   FROM table1
   INNER JOIN table2
   ON table1.fruit_id = table2.fruit_id
   WHERE table1.fruit = ?
', undef, 'apple');

[download]
This will yield: 
[ [a1], [a2], [a3] ]

[download]
You can instead use selectcol_arrayref to return [a1, a2, a3].

No apple, but we already know we want apples.

[Updated, had to confirm exact return structure of a one column set from selectall_arrayref()]

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re: DBI fetchall_arrayref by jeffa
in thread DBI fetchall_arrayref by kiat

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