I've done this at least a couple of times, it's not rocket science.

Something along the lines of... 

my $number_of_levels = 5;
my $query = 'T1.name AS lev1';
my $join = '';
my $old_table = 'T1';
for(2..$number_of_levels) {
  $query .= ", T$_.name AS lev$_";
  $join .= " LEFT JOIN tab AS T$_ ON T$_.parentID = $old_table.ID";
  $old_table = "T$_";
}

print $finished_query = "SELECT $query FROM tag AS T1 $join WHERE T1.p
+arentID = 0";

[download]
That should pretty much do it.

                - Ant
                - Some of my best work - (1 2 3)

In reply to Re: generate self join sql with specified depth level by suaveant
in thread generate self join sql with specified depth level by Anonymous Monk

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