if ($concat !~ /\Q$string/) {
   $concat .= " and $string";
}
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_________
broquaint

And, if you are putting other stuff in your regex that you don't want escaped, end the quotemeta with a \E, ie,

if ($concat !~ /other stuff\Q$string\E more other stuff/) {
   $concat .= " and $string";
}
[download]

Scott
Project coordinator of the Generic Model Organism Database Project

my $concat = "good times and fun (times) and bad (times)";

for my $string ('good times', 'bad times', 'fun (times)') {
   # if the index function returns -1, it is not a substring
   if (index($concat, $string) == -1) {
      $concat .= " and $string";
   }
}

print $concat . "\n";
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Scott
Project coordinator of the Generic Model Organism Database Project

Can you do a "SELECT DISTINCT"

In general, this is a bad thing to do. select distinct is a Red Flag. It may mean that you are making the database engine fetch a far larger result set than necessary. After it has fetched all that, you then tell it to filter the results and discard the duplicates. A much better approach would be to write the query correctly so that the distinct modifier becomes unnecessary.

It may mean that you that you need to consider a column that is not referenced specifically in the record set. The workaround may involve using a subselect, which is not available on databases like MySQL. In that case you are out of luck. Nonetheless, your first reflex should be to try and restructure your query. select distinct should be used only as a last resort.

erm, the "you" doesn't refer to scain here, it refers to you :)


print@_{sort keys %_},$/if%_=split//,'= & *a?b:e\f/h^h!j+n,o@o;r$s-t%t#u'

Thanks grinder; that is a good point. If you are doing a select distinct often (which, if you are putting it in code, you probably are), you probably do want to rethink your query. You may even find that in order to rethink your query, you may need to rethink your schema. Have fun :-)

Scott
Project coordinator of the Generic Model Organism Database Project

One more reason to use PostgreSQL.

my %seen;
my $concat = join " and ", grep !$seen{$_}++, @db_string;
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Makeshifts last the longest.