private static void LiftOrderBy(
SelectExpression innerJoinSelectExpression,
SelectExpression targetSelectExpression,
TableExpressionBase innerJoinExpression)
{
var needOrderingChanges
= innerJoinSelectExpression.OrderBy
.Any(x => x.Expression is SelectExpression ||
x.Expression.IsAliasWithColumnExpression() ||
x.Expression.IsAliasWithSelectExpression());
var orderings = innerJoinSelectExpression.OrderBy.ToList();
if (needOrderingChanges)
{
innerJoinSelectExpression.ClearOrderBy();
}
foreach (var ordering in orderings)
{
var orderingExpression = ordering.Expression;
var aliasExpression = ordering.Expression as AliasExpression;
if (aliasExpression?.Alias != null)
{
var columnExpression = aliasExpression.TryGetColumnExpression();
if (columnExpression != null)
{
orderingExpression
= new ColumnExpression(
aliasExpression.Alias,
columnExpression.Property,
columnExpression.Table);
}
}
var index = orderingExpression is SelectExpression
? innerJoinSelectExpression.AddAliasToProjection(innerJoinSelectExpression.Alias + "_" + innerJoinSelectExpression.Projection.Count, orderingExpression)
: innerJoinSelectExpression.AddToProjection(orderingExpression);
var expression = innerJoinSelectExpression.Projection[index];
if (needOrderingChanges)
{
innerJoinSelectExpression.AddToOrderBy(new Ordering(expression.TryGetColumnExpression() ?? expression, ordering.OrderingDirection));
}
var newExpression
= targetSelectExpression.UpdateColumnExpression(expression, innerJoinExpression);
targetSelectExpression.AddToOrderBy(new Ordering(newExpression, ordering.OrderingDirection));
}
if ((innerJoinSelectExpression.Limit == null) &&
(innerJoinSelectExpression.Offset == null))
{
innerJoinSelectExpression.ClearOrderBy();
}
}