internal override SqlExpression VisitMultiset(SqlSubSelect sms)
{
// allow one big-join per query?
if ((this.options & Options.EnableBigJoin) != 0 &&
!this.hasBigJoin && this.canJoin && this.isTopLevel && this.outerSelect != null &&
!MultisetChecker.HasMultiset(sms.Select.Selection) &&
BigJoinChecker.CanBigJoin(sms.Select))
{
sms.Select = this.VisitSelect(sms.Select);
SqlAlias alias = new SqlAlias(sms.Select);
SqlJoin join = new SqlJoin(SqlJoinType.OuterApply, this.outerSelect.From, alias, null, sms.SourceExpression);
this.outerSelect.From = join;
this.outerSelect.OrderingType = SqlOrderingType.Always;
// make joined expression
SqlExpression expr = (SqlExpression)SqlDuplicator.Copy(sms.Select.Selection);
// make count expression
SqlSelect copySelect = (SqlSelect)SqlDuplicator.Copy(sms.Select);
SqlAlias copyAlias = new SqlAlias(copySelect);
SqlSelect countSelect = new SqlSelect(sql.Unary(SqlNodeType.Count, null, sms.SourceExpression), copyAlias, sms.SourceExpression);
countSelect.OrderingType = SqlOrderingType.Never;
SqlExpression count = sql.SubSelect(SqlNodeType.ScalarSubSelect, countSelect);
// make joined collection
SqlJoinedCollection jc = new SqlJoinedCollection(sms.ClrType, sms.SqlType, expr, count, sms.SourceExpression);
this.hasBigJoin = true;
return(jc);
}
else
{
return(QueryExtractor.Extract(sms, this.parentParameters));
}
}
internal override SqlExpression VisitElement(SqlSubSelect elem)
{
return(QueryExtractor.Extract(elem, this.parentParameters));
}