getVar method
Implementation
Future<String?> getVar(String key) async {
final re = await db.select(
'SELECT value, numb FROM "variables" WHERE name=?',
[key],
);
if (re.isEmpty) return null;
final str = re.first['value'] as String;
return (str.isEmpty) ? '${re.first['numb']}' : re.first['value'];
}