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System.Data.Common.CommandTrees Namespace

Provides classes to build expressions that make up a command tree.

Classes

DbAggregate

Implements the basic functionality required by aggregates in a GroupBy clause.

DbAndExpression

Represents the logical AND of two Boolean arguments. This class cannot be inherited.

DbApplyExpression

Represents an apply operation, which is the invocation of the specified function for each element in the specified input set. This class cannot be inherited.

DbArithmeticExpression

Represents an arithmetic operation applied to numeric arguments. Addition, subtraction, multiplication, division, modulo, and negation are arithmetic operations. This class cannot be inherited.

DbBinaryExpression

Implements the basic functionality required by expressions that accept two expression operands.

DbCaseExpression

Represents the When, Then, and Else clauses of the DbCaseExpression. This class cannot be inherited.

DbCastExpression

Represents the type conversion of a single argument to the specified type. This class cannot be inherited.

DbCommandTree

An immutable class that implements the basic functionality for the Query, Insert, Update, Delete, and function invocation command tree types.

DbComparisonExpression

Represents a comparison operation applied to two arguments. Equality, greater than, greater than or equal, less than, less than or equal, and inequality are comparison operations. This class cannot be inherited.

DbConstantExpression

Represents different kinds of constants (literals). This class cannot be inherited.

DbCrossJoinExpression

Represents an unconditional join operation between the given collection arguments. This class cannot be inherited.

DbDeleteCommandTree

Represents a single row delete operation expressed as a command tree. This class cannot be inherited.

DbDerefExpression

Represents the an expression that retrieves an entity based on the specified reference. This class cannot be inherited.

DbDistinctExpression

Removes duplicate elements from the specified set argument. This class cannot be inherited.

DbElementExpression

Represents the conversion of the specified set argument to a singleton. This class cannot be inherited.

DbEntityRefExpression

Represents an expression that extracts a reference from the underlying entity instance. This class cannot be inherited.

DbExceptExpression

Represents the set subtraction operation between the left and right operands. This class cannot be inherited.

DbExpression

Represents the base type for all expressions.

DbExpressionBinding

Represents an input set to relational expressions such as DbFilterExpression, DbProjectExpression, and DbJoinExpression. This class cannot be inherited.

DbExpressionVisitor

Defines the basic functionality that should be implemented by visitors that do not return a result value.

DbExpressionVisitor<TResultType>

Defines the basic functionality that should be implemented by visitors that return a result value of a specific type.

DbFilterExpression

Represents a predicate applied to filter an input set. This produces the set of elements that satisfy the predicate. This class cannot be inherited.

DbFunctionAggregate

Supports standard aggregate functions, such as MIN, MAX, AVG, SUM, and so on. This class cannot be inherited.

DbFunctionCommandTree

Represents the invocation of a database function.

DbFunctionExpression

Represents an invocation of a function. This class cannot be inherited.

DbGroupAggregate

Represents a collection of elements that compose a group.

DbGroupByExpression

Represents a group by operation. A group by operation is a grouping of the elements in the input set based on the specified key expressions followed by the application of the specified aggregates. This class cannot be inherited.

DbGroupExpressionBinding

Defines the binding for the input set to a DbGroupByExpression. This class cannot be inherited.

DbInsertCommandTree

Represents a single row insert operation expressed as a command tree. This class cannot be inherited.

DbIntersectExpression

Represents the set intersection operation between the left and right operands. This class cannot be inherited.

DbIsEmptyExpression

Represents an empty set determination applied to a single set argument. This class cannot be inherited.

DbIsNullExpression

Represents null determination applied to a single argument. This class cannot be inherited.

DbIsOfExpression

Represents the type comparison of a single argument against the specified type. This class cannot be inherited.

DbJoinExpression

Represents an inner, left outer, or full outer join operation between the given collection arguments on the specified join condition.

DbLambda

Represents a Lambda function that can be invoked to produce a DbLambdaExpression.

DbLambdaExpression

Allows the application of a lambda function to arguments represented by DbExpression objects.

DbLikeExpression

Represents a string comparison against the specified pattern with an optional escape string. This class cannot be inherited.

DbLimitExpression

Represents the restriction of the number of elements in the argument collection to the specified limit value.

DbModificationClause

Specifies a single clause in an insert or update modification operation.

DbModificationCommandTree

Represents a data manipulation language (DML) operation expressed as a command tree.

DbNewInstanceExpression

Represents the construction of a new instance of a given type, including set and record types. This class cannot be inherited.

DbNotExpression

Represents the logical NOT of a single Boolean argument. This class cannot be inherited.

DbNullExpression

Represents a reference to a typed null literal. This class cannot be inherited.

DbOfTypeExpression

Represents the retrieval of elements of the specified type from the given set argument. This class cannot be inherited.

DbOrExpression

Represents the logical OR of two Boolean arguments. This class cannot be inherited.

DbParameterReferenceExpression

Represents a reference to a parameter declared on the command tree that contains this expression. This class cannot be inherited.

DbProjectExpression

Represents the projection of a given input set over the specified expression. This class cannot be inherited.

DbPropertyExpression

Provides methods and properties for retrieving an instance property. This class cannot be inherited.

DbQuantifierExpression

Represents a quantifier operation of the specified kind over the elements of the specified input set. This class cannot be inherited.

DbQueryCommandTree

Represents a query operation expressed as a command tree. This class cannot be inherited.

DbRefExpression

Represents a strongly typed reference to a specific instance within an entity set. This class cannot be inherited.

DbRefKeyExpression

Represents the retrieval of the key value (in its structural form) from the underlying reference value. This class cannot be inherited.

DbRelationshipNavigationExpression

Represents the navigation of a relationship. This class cannot be inherited.

DbScanExpression

Represents a scan over an entity set or relationship set, as indicated by the Target property. This class cannot be inherited.

DbSetClause

Specifies the clause in a modification operation that sets the value of a property. This class cannot be inherited.

DbSkipExpression

Skips a specified number of elements in the input set. DbSkipExpression can only be used after the input collection has been sorted as specified by the sort keys.

DbSortClause

Specifies a sort key that can be used as part of the sort order in a DbSortExpression. This class cannot be inherited.

DbSortExpression

Represents a sort operation applied to the elements of the specified input set based on the given sort keys. This class cannot be inherited.

DbTreatExpression

Represents a type conversion operation applied to a polymorphic argument. This class cannot be inherited.

DbUnaryExpression

Implements the basic functionality required by expressions that accept a single expression argument.

DbUnionAllExpression

Represents the set union (without duplicate removal) operation between the left and right operands. This class cannot be inherited.

DbUpdateCommandTree

Represents a single-row update operation expressed as a command tree. This class cannot be inherited.

DbVariableReferenceExpression

Represents a reference to a variable that is currently in scope. This class cannot be inherited.

DefaultExpressionVisitor

Visits each element of an expression tree from a given root expression. If any element changes, the tree is rebuilt back to the root and the new root expression is returned; otherwise the original root expression is returned.

Enums

DbExpressionKind

Contains values that each expression class uses to denote the operation it represents. The ExpressionKind property of an DbExpression can be retrieved to determine which operation that expression represents.

Remarks

A command trees is an object model representation of a query that can be used to represent query, update, insert, and delete commands in the ADO.NET Entity Data Model (EDM) and storage metadata.