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How do I sort on more than one column?

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Contributed by Russ on Jul 23, 2000 at 23:51 UTC
Q&A  > sorting


Answer: How do I sort on more than one column?
contributed by Russ

The comparison operators return 0 when the operands are equal. So, using the || operator, we can sort first by one column, then another (as many as we want).

@data = ( [qw(Bubba brutalski 20)], [qw(Bubba brutalski 10)], [qw(JoeBob brutalski 20)], [qw(Jethro brutalski 20)], [qw(Junior brutalski 20)], ); # Sorted by Name (Last, First) @ByName = sort {$a->[1] cmp $b->[1] || $a->[0] cmp $b->[0]} @data; # Sorted by Name, then score @FullSort = sort {$a->[1] cmp $b->[1] || $a->[0] cmp $b->[0] || $a->[2] <=> $b->[2]} @data;
In the second example above, @FullSort looks like:
( [Bubba, brutalski, 10], [Bubba, brutalski, 20], [Jethro, brutalski, 20], [JoeBob, brutalski, 20], [Junior, brutalski, 20] )
because it is sorted by Last Name, then First Name, then Score.

Russ

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