This is exactly the problem placeholders are intended to solve. With placeholders, you just mark where you want to insert data into your SQL statement and the database interface layers take care of passing that data to the database where it belongs. I always use placeholders and have never had to worry about quoting.

Look in the Tutorials section. There are plenty of tutorials that explain how to use DBI with placeholders.

Also, you'll get faster and more accurate answers to your questions if you give all the details you can up front instead of being miserly with information about what you are really trying to do.