You can pass null to Database.UseTransaction() to clear Entity Framework’s knowledge of the current transaction. New BloggingContext(conn, contextOwnsConnection: false)) SqlCommand.CommandText Blogs SET Rating = 5" + Using (var sqlTxn = conn.BeginTransaction()) Using (var conn = new SqlConnection(".")) You take responsibility for committing or rolling back the transaction and for calling Dispose() on it, as well as for closing and disposing the database connection. All such operations are executed within one transaction. Then you are free to execute database operations either directly on the SqlConnection itself, or on the DbContext. Using (var context = new BloggingContext(conn, contextOwnsConnection: false))įurthermore, you must start the transaction yourself (including the IsolationLevel if you want to avoid the default setting) and let Entity Framework know that there is an existing transaction already started on the connection (see line 33 below). This is important as it informs Entity Framework that it should not close the connection when it is done with it (for example, see line 4 below): using (var conn = new SqlConnection(".")) The contextOwnsConnection flag must be set to false when called in this scenario. Using (var dbContextTransaction = Blogs SET Rating = 5" + Using (var context = new BloggingContext()) Static void StartOwnTransactionWithinContext() One easy way to accomplish this is the using(…) syntax which will automatically call Dispose() when the using block completes: using System The DbContextTransaction is meant to be disposed once it has been committed or rolled back. Both overrides return a DbContextTransaction object which provides Commit() and Rollback() methods which perform commit and rollback on the underlying store transaction. Database.UseTransaction() : which allows the DbContext to use a transaction which was started outside of the Entity Framework.Ĭombining several operations into one transaction within the same contextĭatabase.BeginTransaction() has two overrides – one which takes an explicit IsolationLevel and one which takes no arguments and uses the default IsolationLevel from the underlying database provider.It also allows the user to more easily specify the isolation level for the transaction. Database.BeginTransaction() : An easier method for a user to start and complete transactions themselves within an existing DbContext – allowing several operations to be combined within the same transaction and hence either all committed or all rolled back as one.Starting with EF6 the framework now provides: The limitation of only accepting closed connections was removed in Entity Framework 6. In addition, API calls which contacted the database would fail if you had started a transaction on the underlying database connection on your own. Since a transaction can only be started on an open connection, this meant that the only way a user could wrap several operations into one transaction was either to use a TransactionScope or use the ObjectContext.Connection property and start calling Open() and BeginTransaction() directly on the returned Entit圜onnection object. Prior to EF6 Entity Framework insisted on opening the database connection itself (it threw an exception if it was passed a connection that was already open). However some users require greater control over their transactions – this is covered in the following sections. This default functionality is suitable for a lot of users and if so there is no need to do anything different in EF6 just write the code as you always did. By default, for instance, on SQL Server this is READ COMMITTED.Įntity Framework does not wrap queries in a transaction. In either case, the isolation level of the transaction is whatever isolation level the database provider considers its default setting. Also in EF6 execution of stored procedures included in the model through APIs such as ObjectContext.ExecuteFunction() does the same (except that the default behavior cannot at the moment be overridden). There are overloads of this method that allow you to override this behavior if you wish. Starting with EF6 Database.ExecuteSqlCommand() by default will wrap the command in a transaction if one was not already present. When you execute another such operation a new transaction is started. This transaction lasts only long enough to execute the operation and then completes. In all versions of Entity Framework, whenever you execute SaveChanges() to insert, update or delete on the database the framework will wrap that operation in a transaction. This document will describe using transactions in EF6 including the enhancements we have added since EF5 to make working with transactions easy. If you are using an earlier version, some or all of the information does not apply. discussed in this page were introduced in Entity Framework 6. EF6 Onwards Only - The features, APIs, etc.
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