Can I install microsoft sql in linode?

Here's a resource that might be just what you're looking for:

• Quickstart: Install SQL Server and create a database on Ubuntu

This guide will walk you through the process of installing Microsoft SQL Server on an Ubuntu system.

Additionally, if you're interested in specific information about running Microsoft SQL Server Express on a Linode, you might find this answered Community question to be informative:

• Running SQL Server Express on a Linode