transactions

问题 is it possible to get current Spring transaction in JUnit? I want to test JPA in DAO. And DAO do not have transactions. In tests spring create transaction for every method. I want transaction to be commited somewhere in the middle of test. Need it to test DB status. Only solution I found is to create @Rule for every method. 回答1: You can use TestTransaction in order to manage spring test transactions: TestTransaction.flagForCommit(); TestTransaction.end(); This will flag the current

问题 Transaction is an atomic process but that means we need to read the data prior to incrementing it. We can easily implement ServerValue.increment(1) in Node.js but in Flutter we only have ServerValue.timestamp according to the documentation here although the Google documentation has it And so far I search I haven't found anything yet. Am I missing something? 来源： https://stackoverflow.com/questions/63275901/does-realtime-database-has-atomic-increment-method-for-flutter-like-servervalue

问题 I'm conducting a data analytics project for a small supermarket and the IT guy sent me a file (.db0 extension) of their transaction details, but I'm unable to read it. Apparently it comes from the IBM 4690 Supermarket Application controller. I've done internet searches and nothing helpful comes up. The guy that sent it to me said he has never had to convert or read it into CSV or any other file format, so he can't provide any assistance. 回答1: .dbo files are transaction sumary log file. You

问题 I'm conducting a data analytics project for a small supermarket and the IT guy sent me a file (.db0 extension) of their transaction details, but I'm unable to read it. Apparently it comes from the IBM 4690 Supermarket Application controller. I've done internet searches and nothing helpful comes up. The guy that sent it to me said he has never had to convert or read it into CSV or any other file format, so he can't provide any assistance. 回答1: .dbo files are transaction sumary log file. You

问题 This is my Repository layer: class RepositoryImpl implements Repository{ @Override public Serializable saveOrUpdate(Object obj) { return getSession().save(obj); } @Override public Object get(Class refClass, Serializable key) { return getSession().get(refClass, key); } } This is my Service layer: class ServiceImpl implements Service{ @Autowired Repository repository; @Override @Transactional public Object findUserById(Serializable key) { // TODO Auto-generated method stub return repository.get

问题 I have been stuck for a while to make Spring rollback a transaction when a checked exception is thrown using @Transactional(rollbackFor) . Here is my code: The data access class: @Repository public class CustomerDao { @Autowired private SessionFactory sessionFactory; public void willRollback() throws CheckedException { sessionFactory.getCurrentSession().persist(new SpringCustomer(null, "roll back")); throw new CheckedException(); } } Where CheckedException is just a simple checked exception:

问题 I feel like I should know this, but I can't find anything that specifically outlines this, so here goes. The documentation for SQL Server describes REPEATABLE READ as: Specifies that statements cannot read data that has been modified but not yet committed by other transactions and that no other transactions can modify data that has been read by the current transaction until the current transaction completes This makes sense, but what actually happens when one of these situation arises? If,

问题 I feel like I should know this, but I can't find anything that specifically outlines this, so here goes. The documentation for SQL Server describes REPEATABLE READ as: Specifies that statements cannot read data that has been modified but not yet committed by other transactions and that no other transactions can modify data that has been read by the current transaction until the current transaction completes This makes sense, but what actually happens when one of these situation arises? If,

问题 In my code there are transactions to handle: using (var scope = new TransactionScope()) { repo1.SaveSomething(); repo2.SaveAnythingElse(); scope.Complete(); } Inside repo1 and repo2 functions create their own db context with using, and dispose them, the transactions worked like a charm. Now I add another code like this, and it begins to drop an exception: The underlying provider failed on Open. (EntityFramework) Network access for Distributed Transaction Manager (MSDTC) has been disabled.

问题 After executing the below code, create table t(id int primary key); insert into t values (5),(10); -- session 1 start transaction; select * from t where id > 8 for share; -- session 2 start transaction; insert into t values(6); -- is blocked the output of select * from performance_schema.data_locks is: +--------+---------------------------------------+-----------------------+-----------+----------+---------------+-------------+----------------+-------------------+------------+----------------