* add support for reverse

[bin.git] / db-hash

diff --git a/db-hash b/db-hash
index db7066e6110fc4796b7b4d4a4c2417ee36e4f400..d9ad8af30d0746c9b89e9e35da16ef65ac5efcfb 100755 (executable)
--- a/db-hash
+++ b/db-hash
@@ -57,6 +57,11 @@ Output the key as well as the value. (Off by default)
 If a key doesn't exist in the database, output a newline. (Forced on
 when --include-key set)
 
+=item B<--reverse,-r>
+
+Reverse the database (value looks up keys instead); only useful during
+creation/update
+
 =item B<--debug, -d>
 
 Debug verbosity. (Default 0)
@@ -89,12 +94,14 @@ my %options = (debug           => 0,
               dump            => 0,
 #             include_key     => 0,
               missing_newline => 1,
+              reverse         => 0,
               );
 
 GetOptions(\%options,
           'create|c','update|u',
           'dump|D',
           'include_key|include-key|k!',
+          'reverse|r!',
           'missing_newline|missing-newline|n!',
           'debug|d+','help|h|?','man|m');
 
@@ -130,23 +137,19 @@ if (not defined $options{include_key}) {
 }
 
 
-if ($options{update}) {
+if ($options{update} or $options{create}) {
     my %fast_db;
     while (<STDIN>) {
        chomp;
        my ($key,@val) = split /\t/;
-       $fast_db{$key} = [make_list($fast_db{$key} // [],@val)];
-    }
-    for my $key (keys %fast_db) {
-       $t_db{$key} = $fast_db{$key};
-    }
-}
-elsif ($options{create}) {
-    my %fast_db;
-    while (<STDIN>) {
-       chomp;
-       my ($key,@val) = split /\t/;
-       $fast_db{$key} = [make_list($fast_db{$key} // [],@val)];
+       if ($options{reverse}) {
+           for my $val_key (@val) {
+               $fast_db{$val_key} = [make_list($fast_db{$val_key})//[],$key];
+           }
+       }
+       else {
+           $fast_db{$key} = [make_list($fast_db{$key} // [],@val)];
+       }
     }
     for my $key (keys %fast_db) {
        $t_db{$key} = $fast_db{$key};
@@ -154,7 +157,7 @@ elsif ($options{create}) {
 }
 elsif ($options{dump}) {
     for my $key (keys %t_db) {
-       print "$key:".join("\t",make_list($t_db{$key}))."\n";
+       print "$key\t".join("\t",make_list($t_db{$key}))."\n";
     }
 }
 else {