orderBy method
Adds an ORDER BY clause for column and direction.
Implementation
QueryBuilder orderBy(String column, [String direction = 'ASC']) {
final dir = direction.toUpperCase();
if (dir != 'ASC' && dir != 'DESC') {
throw ArgumentError('Order direction must be ASC or DESC');
}
_orderBy = '${_quoteIdentifier(column)} $dir';
return this;
}