When you first install SambaPOS it will setup Compact SQL 4.0 database. Compact SQL is fast and lightweight (2.5MB) single user database engine. If you cancelled it during installation or your windows version does not support Compact SQL 4.0, SambaPOS will automatically switch to internal TXT Database. TXT database is only for demonstration.
If you want to use SambaPOS on a production environment you should operate it on Compact SQL, SQL Express or SQL Server
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