[dordnung]

You just have to add:

"stamm_sqlite"
	{
		"driver"			"sqlite"
		"host"    			"localhost"
		"database"   		"stamm-sqlite"
		"user"    			"root"
		"pass"   			""
	}

so:

"Databases"
{
    "driver_default"        "mysql"
    
    "default"
    {
        "driver"            "default"
        "host"                "localhost"
        "database"            "sourcemod"
        "user"                "root"
        "pass"                ""
        //"timeout"            "0"
        //"port"            "0"
    }
    
    "storage-local"
    {
        "driver"            "sqlite"
        "database"            "sourcemod-local"
    }

    "clientprefs"
    {
        "driver"            "sqlite"
        "host"                "localhost"
        "database"            "clientprefs-sqlite"
        "user"                "root"
        "pass"                ""
        //"timeout"            "0"
        //"port"            "0"
    }
    "stamm_sqlite"
	{
		"driver"			"sqlite"
		"host"    			"localhost"
		"database"   		"stamm-sqlite"
		"user"    			"root"
		"pass"   			""
	}
}