Make the memory database use a set name so it's safe to defer

main.go

@@ -288,10 +288,16 @@ func main() {
 		}
 	}(conn)
 
-	mem, err = sql.Open("sqlite3", ":memory:?cache=shared&mode=memory")
+	mem, err = sql.Open("sqlite3", "file:bgnsessiondb?cache=shared&mode=memory")
 	if err != nil {
 		log.Fatalln("[FATAL] Cannot open session database:", err)
 	}
+	defer func(mem *sql.DB) {
+		err := mem.Close()
+		if err != nil {
+			log.Println("[ERROR] Unknown in main() mem defer:", err)
+		}
+	}(mem)
 
 	_, err = mem.Exec("CREATE TABLE sessions (sessionid INTEGER PRIMARY KEY AUTOINCREMENT, session TEXT NOT NULL, id INTEGER NOT NULL, device TEXT NOT NULL DEFAULT '?')")
 	if err != nil {