first method
Implementation
Future<List?> first() async {
if (!currentQuery.isQuery()) {
throw Exception('Dblayer@first Is nessesary query');
}
final rows = await executor.query(currentQuery.toSql(isFirst: true),
currentQuery.buildSubstitutionValues());
if (rows.isNotEmpty) {
return rows[0];
} else {
return null;
}
}