Placeholders are definitely the way to go. However there is another approach that can be useful for situations where you can't use palceholders. The only example that comes to mind of a time where you can't use placeholders is "selet * from foo where bar in (?)" where you want to specify a list with an unknown number of elements for ?.

The DBH quote function will quote a variable apropriately for the DB that your handle is connected to, escaping all necessary metacharacters, etc.... 

my $s=$dbh->quote($a);

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In reply to RE: DBI Quoting question by lhoward
in thread DBI Quoting question by perlcgi

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