As pointed out by many others, you may want to use placeholders, especially if you will be executing the same query several times with different data during the lifespan of the database connection.

That said, placeholders do not necessarily have a place in once-off queries. What you absolutely MUST do when placing your data inline like this, is quote your data using the $dbh->quote() method. Make it a habit, even when you trust your variables, because you may reuse the code later.

Not only does ->quote() place quotation marks around your strings (failure to do so will make the query fail) but it will also escape potentially harmful characters that could be injected by a hacker. 

my $name = "; DROP DATABASE mysql;";
my $sth = $dbh->prepare("INSERT INTO names (name) values ('$name')");
$sth->execute;

[download]
This script won't insert anything, but if you are logged into MySQL with sufficient privileges it will ruin your day. Protecting yourself is easy: 
my $name = "; DROP DATABASE mysql;";
my $sth = $dbh->prepare("INSERT INTO names (name) values (".$dbh->quot
+e($name).")");
$sth->execute;

[download]
Now the evil name will be inserted into the table as expected.

Google "SQL Injection".

-- Time flies when you don't know what you're doing

In reply to Re: Problem with DBI and MySQL by FloydATC
in thread Problem with DBI and MySQL by joemidnite

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