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//---------------------------------------------------------------------
// <copyright file="DbDeleteCommandTree.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//
// @owner Microsoft, Microsoft
// @backupOwner Microsoft
//---------------------------------------------------------------------
using System;
using System.Collections.Generic;
using System.Data.Metadata.Edm;
using System.Data.Common.CommandTrees.Internal;
using System.Data.Common.Utils;
namespace System.Data.Common.CommandTrees
{
/// <summary>
/// Represents a single row delete operation expressed as a canonical command tree.
/// </summary>
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1709:IdentifiersShouldBeCasedCorrectly", MessageId = "Db")]
public sealed class DbDeleteCommandTree : DbModificationCommandTree
{
private readonly DbExpression _predicate;
internal DbDeleteCommandTree(MetadataWorkspace metadata, DataSpace dataSpace, DbExpressionBinding target, DbExpression predicate)
: base(metadata, dataSpace, target)
{
EntityUtil.CheckArgumentNull(predicate, "predicate");
this._predicate = predicate;
}
/// <summary>
/// Gets an <see cref="DbExpression"/> that specifies the predicate used to determine which members of the target collection should be deleted.
/// </summary>
/// <remarks>
/// The predicate can include only the following elements:
/// <list>
/// <item>Equality expression</item>
/// <item>Constant expression</item>
/// <item>IsNull expression</item>
/// <item>Property expression</item>
/// <item>Reference expression to the target</item>
/// <item>And expression</item>
/// <item>Or expression</item>
/// <item>Not expression</item>
/// </list>
/// </remarks>
public DbExpression Predicate
{
get
{
return _predicate;
}
}
internal override DbCommandTreeKind CommandTreeKind
{
get { return DbCommandTreeKind.Delete; }
}
internal override bool HasReader
{
get
{
// a delete command never returns server-gen values, and
// therefore never returns a reader
return false;
}
}
internal override void DumpStructure(ExpressionDumper dumper)
{
base.DumpStructure(dumper);
if (this.Predicate != null)
{
dumper.Dump(this.Predicate, "Predicate");
}
}
internal override string PrintTree(ExpressionPrinter printer)
{
return printer.Print(this);
}
}
}
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