MySQL_class: Database Error occured!

 CODE: -1
 DESC: N/A
 FILE: index.php
QUERY: select * from categories where parent_id=0 and status='Y' and deleted='N' and cat_type='sell' group by name order by name
 QCNT: 2
 INFO: QueryResult('select * from categories where parent_id=0 and status='Y' and deleted='N' and cat_type='sell' group by name order by name ') failed!

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PHP v5.6.40 / MySQL Class v0.36