public override DbExpression Visit(DbGroupByExpression expression)
{
EntityUtil.CheckArgumentNull(expression, "expression");
DbExpression result = expression;
DbGroupExpressionBinding newInput = this.VisitGroupExpressionBinding(expression.Input);
this.EnterScope(newInput.Variable);
IList <DbExpression> newKeys = this.VisitExpressionList(expression.Keys);
this.ExitScope();
this.EnterScope(newInput.GroupVariable);
IList <DbAggregate> newAggs = this.VisitList <DbAggregate>(expression.Aggregates, this.VisitAggregate);
this.ExitScope();
if (!object.ReferenceEquals(expression.Input, newInput) ||
!object.ReferenceEquals(expression.Keys, newKeys) ||
!object.ReferenceEquals(expression.Aggregates, newAggs))
{
RowType groupOutput =
TypeHelpers.GetEdmType <RowType>(TypeHelpers.GetEdmType <CollectionType>(expression.ResultType).TypeUsage);
var boundKeys = groupOutput.Properties.Take(newKeys.Count).Select(p => p.Name).Zip(newKeys).ToList();
var boundAggs = groupOutput.Properties.Skip(newKeys.Count).Select(p => p.Name).Zip(newAggs).ToList();
result = CqtBuilder.GroupBy(newInput, boundKeys, boundAggs);
}
NotifyIfChanged(expression, result);
return(result);
}
/// <summary>
/// Visitor pattern method for <see cref="DbGroupByExpression"/>.
/// </summary>
/// <param name="expression">The DbExpression that is being visited.</param>
/// <exception cref="ArgumentNullException"><paramref name="expression"/> is null</exception>
public override void Visit(DbGroupByExpression expression)
{
// #433613: PreSharp warning 56506: Parameter 'expression' to this public method must be validated: A null-dereference can occur here.
EntityUtil.CheckArgumentNull(expression, "expression");
VisitGroupExpressionBindingPre(expression.Input);
VisitExpressionList(expression.Keys);
VisitGroupExpressionBindingMid(expression.Input);
VisitAggregateList(expression.Aggregates);
VisitGroupExpressionBindingPost(expression.Input);
}
/// <summary> /// Typed visitor pattern method for DbGroupByExpression. /// </summary> /// <param name="expression">The DbGroupByExpression that is being visited.</param> /// <returns>An instance of TResultType.</returns> public abstract TResultType Visit(DbGroupByExpression expression);
/// <summary> /// Visitor pattern method for DbGroupByExpression. /// </summary> /// <param name="expression">The DbGroupByExpression that is being visited.</param> public abstract void Visit(DbGroupByExpression expression);
