[FIX] ranklib.php: Fix bug where parentId column ambiguity caused SQL error
*To resolve the SQL error caused by parentId column ambiguity, the query now explicitly specifies which table's parentId
column is being referred to by including (a.parentId = 0 OR tf.parentId = 0)
in the WHERE clause, we ensure that the condition is applied correctly to the respective table's parentId
column.
Edited by Marc Laporte