transactions

问题 I need to realize transaction under two models (using two separated bounded contexts). So code like this: using (TransactionScope scope = new TransactionScope()) { //Operation 1 using(var context1 = new Context1()) { context1.Add(someCollection1); context1.SaveChanges(); } //Operation 2 using(var context2 = new Context2()) { context2.Add(someCollection2); context2.SaveChanges(); } scope.Complete(); } return the exception: An ambient transaction has been detected. Entity Framework Core does

问题 I need to realize transaction under two models (using two separated bounded contexts). So code like this: using (TransactionScope scope = new TransactionScope()) { //Operation 1 using(var context1 = new Context1()) { context1.Add(someCollection1); context1.SaveChanges(); } //Operation 2 using(var context2 = new Context2()) { context2.Add(someCollection2); context2.SaveChanges(); } scope.Complete(); } return the exception: An ambient transaction has been detected. Entity Framework Core does

问题 I have a TSQL script that does a lot of database structure adjustments but it's not really safe to just let it go through when something fails. to make things clear: using MS SQL 2005 it's NOT a stored procedure, just a script file (.sql) what I have is something in the following order BEGIN TRANSACTION ALTER Stuff GO CREATE New Stuff GO DROP Old Stuff GO IF @@ERROR != 0 BEGIN PRINT 'Errors Found ... Rolling back' ROLLBACK TRANSACTION RETURN END ELSE PRINT 'No Errors ... Committing changes'

问题 What is the preferable way to write Delphi database applications using transactions and also data-aware components? I have to write a client app that access InnoDB tables, and do some master-detail kind of things inside transactions. After doing some research on transactions (from general point-of-view), then I humbly make a conclusion that non data-aware components and hand-coded SQL would be the "perfect match" of transactions; But the data-aware components wouldn't be. They don't seem to

问题 What is the preferable way to write Delphi database applications using transactions and also data-aware components? I have to write a client app that access InnoDB tables, and do some master-detail kind of things inside transactions. After doing some research on transactions (from general point-of-view), then I humbly make a conclusion that non data-aware components and hand-coded SQL would be the "perfect match" of transactions; But the data-aware components wouldn't be. They don't seem to

问题 Hi i am using the transaction-per-request (session-in-view) pattern for an asp.net web application. I have a couple of points in the application where i want to Save an NHibernate managed entity and then do a couple of more inserts and updates using common sql. These inserts/updates depend on the ID that the NH saved entity will take. The problem is that the generated id does not exist in the transactions' scope. If i force a flush/commit the id is persisted but if the inserts/updates fail i

问题 I have question regarding what purpose we are using SELECT FOR UDPATE ? What does it do exactly? I have 2 tables, from that I need to select rows from table and update the same rows. For example: Select Query SELECT * from t1 WHERE city_id=2 for update Update Query UPDATE t1 SET final_balance = final_balance - 100 WHERE city_id ='2' My question - Does this really lock the read operation till my update is done, or what does it exactly deal with? My idea is nobody can read/update from/to this

问题 I have question regarding what purpose we are using SELECT FOR UDPATE ? What does it do exactly? I have 2 tables, from that I need to select rows from table and update the same rows. For example: Select Query SELECT * from t1 WHERE city_id=2 for update Update Query UPDATE t1 SET final_balance = final_balance - 100 WHERE city_id ='2' My question - Does this really lock the read operation till my update is done, or what does it exactly deal with? My idea is nobody can read/update from/to this

问题 I have question regarding what purpose we are using SELECT FOR UDPATE ? What does it do exactly? I have 2 tables, from that I need to select rows from table and update the same rows. For example: Select Query SELECT * from t1 WHERE city_id=2 for update Update Query UPDATE t1 SET final_balance = final_balance - 100 WHERE city_id ='2' My question - Does this really lock the read operation till my update is done, or what does it exactly deal with? My idea is nobody can read/update from/to this

问题 I have question regarding what purpose we are using SELECT FOR UDPATE ? What does it do exactly? I have 2 tables, from that I need to select rows from table and update the same rows. For example: Select Query SELECT * from t1 WHERE city_id=2 for update Update Query UPDATE t1 SET final_balance = final_balance - 100 WHERE city_id ='2' My question - Does this really lock the read operation till my update is done, or what does it exactly deal with? My idea is nobody can read/update from/to this