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System.Data.Linq Namespace

The System.Data.Linq namespace contains classes that support interaction with relational databases in LINQ to SQL applications.

LINQ to SQL is a technology that provides a run-time infrastructure for managing relational data as objects. For more information, see LINQ to SQL.

Public classBinaryRepresents an immutable block of binary data.
Public classChangeConflictCollectionReturns a collection of objects involved in concurrency conflicts.
Public classChangeConflictExceptionThrown when an update fails because database values have been updated since the client last read them.
Public classChangeSetProvides a container to hold changes.
Public classCompiledQueryProvides for compilation and caching of queries for reuse.
Public classDataContextRepresents the main entry point for the LINQ to SQL framework.
Public classDataLoadOptionsProvides for immediate loading and filtering of related data.
Public classDBConvertInfrastructure. Used internally to convert one type to another.
Public classDuplicateKeyExceptionThrown when an attempt is made to add an object to the identity cache by using a key that is already being used.
Public classEntitySet<TEntity>Provides for deferred loading and relationship maintenance for the collection side of one-to-many and one-to-one relationships in a LINQ to SQL applications. 
Public classForeignKeyReferenceAlreadyHasValueExceptionRepresents errors that occur when an attempt is made to change a foreign key when the entity is already loaded.
Public classMemberChangeConflictRepresents a situation in which an attempted update fails because member values have been updated since the client last read them.
Public classObjectChangeConflictRepresents an update attempt with one or more optimistic concurrency conflicts.
Public classTable<TEntity>Represents a table for a particular type in the underlying database.

Public structureEntityRef<TEntity>Provides for deferred loading and relationship maintenance for the singleton side of a one-to-many relationship in a LINQ to SQL application.
Public structureLink<T>Used to enable deferred loading of individual properties (similar to EntityRef<TEntity>).
Public structureModifiedMemberInfoHolds values of members that have been modified in LINQ to SQL applications.

Public interfaceIExecuteResultProvides access to the return value or results of executing a query.
Public interfaceIFunctionResultProvides access to the return value of a function.
Public interfaceIMultipleResultsRepresents the results of mapped functions or queries with variable return sequences.
Public interfaceISingleResult<T>Represents the result of a mapped function that has a single return sequence.
Public interfaceITableUsed for weakly typed query scenarios.

Public enumerationChangeActionDescribes the type of change the entity will undergo when changes are submitted to the database.
Public enumerationConflictModeSpecifies when concurrency conflicts should be reported.
Public enumerationRefreshModeDefines how the Refresh method handles optimistic concurrency conflicts.