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System.Data.Common.CommandTrees.ExpressionBuilder Namespace

Provides a command tree API.

Classes

DbExpressionBuilder

Provides an API to construct DbExpressions and allows that API to be accessed as extension methods on the expression type itself.

EdmFunctions

Provides an API to construct DbExpression s that invoke canonical EDM functions, and allows that API to be accessed as extension methods on the expression type itself.

Row

Provides a constructor-like means of calling NewRow(IEnumerable<KeyValuePair<String,DbExpression>>).

Remarks

The System.Data.Common.CommandTrees.ExpressionBuilder API is used to create expressions, which are represented by DbExpression objects. The command tree API provided by the DbExpressionBuilder class has the following characteristics:

  • Functional: DbExpression objects are constructed using functional patterns that provide a natural flow of construction.

  • Loosely-coupled: A DbExpression object is not bound to any specific command tree and can be used in any context where type agreement is satisfied.

  • Immutable: The API consists entirely of immutable types; mutability may be simulated by substituting new values while rebuilding an expression tree.