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Re: generate self join sql with specified depth level

by suaveant (Parson)
on Dec 22, 2009 at 14:59 UTC ( #813901=note: print w/replies, xml ) Need Help??

in reply to generate self join sql with specified depth level

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 = ' AS lev1'; my $join = ''; my $old_table = 'T1'; for(2..$number_of_levels) { $query .= ", T$ 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";
That should pretty much do it.

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

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