begintransaction

In fact, this exception is clearly written, that is, the session is closed and the hibernate entity cannot be operated. There are many such cases, such as writing errors and logical errors.But let's talk about the lazy mechanism:Delayed

We all know that the one-to-one ing in hibernate mainly has two policies: (1) one-to-one primary key Association (one-way and two-way ). (2) one-to-one foreign key ing (single and bidirectional ). This article mainly explains the two-way problem in

Object status and conversion:   With the above information Hibernate The knowledge of caching. It is easy to understand the state of an object. A: Free State object: When we pass Java Of New When the keyword is used to generate an object, the object

Because of work requirements, data needs to be exchanged between the Excel and MySQL databases, so I searched the internet for how to use VC to Operate Excel. There are basically three implementation methods, one is to use ODBC, one is to use

In my o/R Mapping journey (II), I analyzed people. HBM. xml and talked about why inverse = "true ": In the vehicle management system, an owner owns multiple vehicles. It is represented by Java. util. Set. Inverse is used to identify the

I have heard that hibernate has been around for a long time, but it has not been close to it until recently. I saw a training PPT in xiangji a long time ago. It said that hibernate is applied to the persistent layer, and Hibernate and persistence

This example shows that a unit has multiple departments, and each department has many different employees. During Storage, an employee table and a department table need to be created, stores all department and employee information, and these two

There is a typical one-to-one relationship between people and ID cards. One of the two ways to map one-to-one associations is based on foreign keys and the other is based on primary keys, next, let's first look at the association method based on

Today, instructor Tang teaches full-text retrieval technology. Today, he is studying compass. This framework is an encapsulation of Lucene. However, it is similar to hibernate.However, there are many similarities. So today, the teacher gave us a

Reproduced to: http://www.cnblogs.com/zhenyulu/articles/330494.html ReadUnCommitted is the lowest isolation level. This level of isolation allows reading dirty data that has not been committed by others. In addition, there is still a problem of

Ado.net supports two transaction models. the. Net Framework document is defined as a guide. the transaction Guide describes the database transactions that should be known normally, which affect operations on a single target database. A class

Add, delete, modify, and query hibernate associated objects ------ query, hibernate ------ This blog post is the addition, deletion, modification, and query of hibernate-related objects in the previous blog. the settings of this Code have been

Android 5.X Toolbar + DrawerLayout implement drawer menu Preface ? A Toolbar added by android5.X, which is more flexible and controllable than ActionBar. Due to the poor flexibility of the previous ActionBar, google gradually uses Toolbar to replace

Android -- Fragment introduction and two basic usage methods   Today, when we call ViewPager, we feel that ViewPager + Fragment is more flexible. Therefore, we can sort out the Fragment and try again.  I. Why Fragment?  1. Flexible Layout Fragment

Android learning 8 (use of android fragment) Fragment is a type of UI Fragment that can be embedded in an activity. It allows programs to make more reasonable and full use of the screen space. First, create a flat simulator 1034*600 and use android4.

Android basic getting started -- 2.4.15 simple use of DrawerLayout (Official slide menu)This section introduces: This section introduces the last widget of the basic UI control:DrawerLayout, A slide menu officially provided for usControl, just

Hibernate core interface, hibernate Core Configuration (AnnotationConfiguration) Role: Manage configuration information Objective: To generate SessionFactory You can specify the hibernate configuration file in the configure method. It is

In order to better understand AOP practices and reflect the advantages of AOP, we will always compare OOP with AOP in the following sections. In the end, we will summarize the advantages of AOP compared with OOP, the disadvantages of AOP, and the

According to the content of Microsoft Snapshot isolation, the example is run and a Chinese comment is given. Example The following example shows how to access the locked data to demonstrate the behavior at different isolation levels, not in

Go to: http://bbs.chinaunix.net/archiver/tid-2331601.html[B] Using transactions (C # programming) in three layers of web development [/B] Many database operations require transactions. There are roughly three levels of transactions under Asp.net:(1)