Entitymanager merge not updating erodatings org
If not, you should get the time before the loop into a variable and just set Altert Date to the variable. if it's inside the transaction, the database locking system will take care of concurrency issues.
of course, if you use one (the mssql default is that it uses lock, so it states if you don't override that) in SQL 2008 a new TSQL statement "MERGE" is introduced which performs insert, update, or delete operations on a target table based on the results of a join with a source table.
2) OPTION_2 Stored procedure Stored procedure will not execute synchronously like redis lua, So there also we need sync code to perform that.
3) OPTION_3 Transaction I have used JPA entity Manager like below, thought that before commit no one can update, and before commit i will get the updated object along with modified time (from DB).
It wouldn’t be advisable to try to match this code construction in production code.
The instance you pass in will not be managed (any changes you make will not be part of the transaction - unless you call merge again). My Entity e = new My Entity(); // scenario 1 // tran starts em.persist(e); Some Field(some Value); // tran ends, and the row for some Field is updated in the database // scenario 2 // tran starts e = new My Entity(); em.merge(e); Some Field(another Value); // tran ends but the row for some Field is not updated in the database // (you made the changes *after* merging) // scenario 3 // tran starts e = new My Entity(); My Entity e2 = em.merge(e); e2Some Field(another Value); // tran ends and the row for some Field is updated // (the changes were made to e2, not e) @dma_k: Looks like you're using Hibernate.
I thought I could just do something like this but am worried about possible concurrency problems: UPDATE TOP (10) Human Resources. When you commit the transaction, the update locks will be released.