I'm a software engineer and I'm currently working on a new project. My clients always complain about my trial versions as it takes too much time and resources. I usually install SQL server full edition for my clients but I want to install a lite version or any alternative for my trial edition.
Microsoft ships a special version of SQL Server exactly for this purpose: SQL Server Express LocalDB.
LocalDB installation copies a minimal set of files necessary to start the SQL Server Database Engine. Once LocalDB is installed, you can initiate a connection using a special connection string. When connecting, the necessary SQL Server infrastructure is automatically created and started, enabling the application to use the database without complex configuration tasks.
The client still needs to install this database but it takes much less resources than a full SQL Server. Here are some instructions on how to connect your program with a LocalDB instance.