transactions

问题 Two models, Organization and User, have a 1:many relationship. I have a combined signup form where an organization plus a user for that organization get signed up. The problem I'm experiencing is: When submitting invalid information for the user, it renders the form again, as it should, but the error messages (such as "username can't be blank") for the user are not displayed. The form does work when valid information is submitted and it does display error messages for organization, just not

问题 Two models, Organization and User, have a 1:many relationship. I have a combined signup form where an organization plus a user for that organization get signed up. The problem I'm experiencing is: When submitting invalid information for the user, it renders the form again, as it should, but the error messages (such as "username can't be blank") for the user are not displayed. The form does work when valid information is submitted and it does display error messages for organization, just not

问题 I am facing a deadlock in my MySQL. How can I configure MySQL to restart the transaction automatically when it encounters a deadlock? 回答1: You cannot do that automatically, as the deadlock occurred, because two transactions were trying to modify the same data . If you know that simply retrying the same statements again will be the right thing to do, you need to implement this in your application. However having the database do that automatically would be irresponsible, because there might

问题 We have a ASP.Net web application that connects to its business layer using WCF. Sometimes, I am getting exception when it is performing a huge operation. The interesting part is when I ran it for the first time it was successful. Afterwards it is throwing exception. Exception: The socket connection was aborted. The operation is that it uploads zipcodes into database tables from a csv file. First we read from csv file and make a single lengthy string of zipcodes. This is passed to the stored

问题 I have this strange thing where OnSuccessListener or OnFailureListener stopped being called. Everything works ok but when I turn of mobile data and Wifi non of the OnSuccessListener or OnFailureListener is being called. If I put a breakpoints on the below code ref.set(update)..... the breakpoints are indeed hit but non of the OnSuccessListener or OnFailureListener fires Map<String, String> update = new HashMap<>(); update.put(ByteData.DATA, data); DocumentReference ref = firestore .collection

问题 I have this strange thing where OnSuccessListener or OnFailureListener stopped being called. Everything works ok but when I turn of mobile data and Wifi non of the OnSuccessListener or OnFailureListener is being called. If I put a breakpoints on the below code ref.set(update)..... the breakpoints are indeed hit but non of the OnSuccessListener or OnFailureListener fires Map<String, String> update = new HashMap<>(); update.put(ByteData.DATA, data); DocumentReference ref = firestore .collection

问题 I have two questions about Compound-Statement and Transactions in MySQL. FIRST: There are two notes in MySQL Manual: Note Within all stored programs, the parser treats BEGIN [WORK] as the beginning of a BEGIN ... END block. To begin a transaction in this context, use START TRANSACTION instead. Note Within all stored programs (stored procedures and functions, triggers, and events), the parser treats BEGIN [WORK] as the beginning of a BEGIN ... END block. Begin a transaction in this context

问题 I'm using Hibernate + spring + @Transactional annotations to handle transactions in my application. Transaction manager is declared as follows: <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"> <property name="sessionFactory" ref="sessionFactory"/> </bean> <tx:annotation-driven transaction-manager="transactionManager"/> This works well in most cases, but I've found a problem where I have 2 methods, both annotated @Transactional: package temp

问题 Just a quick question, but is the flush necessary in this code? Note this would be inside of a JPA transaction. User user = new User(); em.persist(user); em.flush; User aUser = em.find(User.class,user.getId()); assert(user.equals(aUser)); Or is will it work without the flush? User user = new User(); em.persist(user); User aUser = em.find(User.class,user.getId()); assert(user.equals(aUser)); Or same question but a little more involved example: User user = em.find(User.class,id); user.setName(

问题 I am working on a online file management project. We are storing references on the database (sql server) and files data on the on file system. We are facing a problem of coordination between file system and database while we are uploading a file and also in case of deleting a file. First we create a reference in the database or store files on file system. The problem is that if I create a reference in the database first and then store a file on file system, but while storing files on the file