A lightweight version of the Express engine designed specifically for developers.
However, there are several "near-portable" solutions and lightweight alternatives that can achieve the same goal. This guide covers how to get as close as possible to a portable SQL Server experience. ms sql server express portable
1. The Best "Near-Portable" Option: SQL Server Express LocalDB A lightweight version of the Express engine designed
If you absolutely cannot install anything on the host computer, you should consider a database that is designed to be truly portable (zero-install). Portable SQL Server - Server Fault ms sql server express portable
