I had a similar problem and solved it by checking the threads that are running. To see the running threads use the following command in mysql command line interface: SHOW PROCESSLIST; It can also be sent from phpMyAdmin if you don’t have access to mysql command line interface. This will display a list of threads … Read more
The only portable way to achieve consistency between rooms and tags and making sure rooms are never returned after they had been deleted is locking them with SELECT FOR UPDATE. However in some systems locking is a side effect of concurrency control, and you achieve the same results without specifying FOR UPDATE explicitly. To solve … Read more
A transaction is a unit of work that you want to treat as “a whole.” It has to either happen in full or not at all. A classical example is transferring money from one bank account to another. To do that you have first to withdraw the amount from the source account, and then deposit … Read more
Just a helpful hint, there is a company called Yodlee.com who provides this data. They do charge for the API. Companies like Mint.com use this API to gather bank and financial account data. Also, checkout https://plaid.com/, they are a similar company Yodlee.com and provide both authentication API for several banks and REST-based transaction fetching endpoints.
ACID is a set of properties that you would like to apply when modifying a database. Atomicity Consistency Isolation Durability A transaction is a set of related changes which is used to achieve some of the ACID properties. Transactions are tools to achieve the ACID properties. Atomicity means that you can guarantee that all of … Read more
From Wikipedia (which has great and detailed examples for this): A non-repeatable read occurs, when during the course of a transaction, a row is retrieved twice and the values within the row differ between reads. and A phantom read occurs when, in the course of a transaction, two identical queries are executed, and the collection … Read more
You can put set xact_abort on before your transaction to make sure sql rolls back automatically in case of error.
What doesn’t make sense: distributed transactions with REST services. REST services by definition are stateless, so they should not be participants in a transactional boundary that spans more than one service. Your user registration use case scenario makes sense, but the design with REST microservices to create User and Wallet data is not good. What … Read more
The answer your question is no – @Transactional will have no effect if used to annotate private methods. The proxy generator will ignore them. This is documented in Spring Manual chapter 10.5.6: Method visibility and @Transactional When using proxies, you should apply the @Transactional annotation only to methods with public visibility. If you do annotate … Read more
Add a try/catch block, if the transaction succeeds it will commit the changes, if the transaction fails the transaction is rolled back: BEGIN TRANSACTION [Tran1] BEGIN TRY INSERT INTO [Test].[dbo].[T1] ([Title], [AVG]) VALUES (‘Tidd130’, 130), (‘Tidd230′, 230) UPDATE [Test].[dbo].[T1] SET [Title] = N’az2′ ,[AVG] = 1 WHERE [dbo].[T1].[Title] = N’az’ COMMIT TRANSACTION [Tran1] END TRY … Read more