Hello monks
I want to select all duplicates from my database. I am using the following:
my $duplicates= $dbh->selectall_arrayref("SELECT ID, Tag1, Tag2, COUNT
+(*) c FROM table GROUP BY Tag1, Tag2 HAVING c > 1");
This identifies if two (or more) entries are duplicates (Tag1 and Tag2 in combination), however it retrieves only the first (?) occurrence, not all duplicated entries. If I have:
1:science:math
2:science:algebra
3:history:math
4:science:math
The select statement returns 1:science:math, not 4:science:math. Is there a way to change it in order to have in my array all duplicates?
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