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In the actual development, we always use paging query. Different database paging SQL methods are different. We can use paging plug-ins to help us separate queries. We only need to care about the data itself, not the place 1. Plug in introduction Configure the paging plug-in in the core configuratio ...

Reprinted from Read the source code of mybatis (8) -- Interceptor 1 Intercetor MyBatis allows you to make intercept calls at some point during the execution of mapped statements. By default, MyBatis allows the use of plug-ins to intercept method calls including: Executor (update, query, flushState ...

The paging tool based on JPA supports multi table Association of native sql, and the generation of conditions only needs to be explicitly annotated on dto. It can simplify development, improve development efficiency, and conform to the development habits of mybatis developers. 1. User defined cond ...

I. Introduction The    StatementHandler is one of the most core interfaces of Mybatis. He has completed the work related to the interaction between Mybatis and database (the interaction between Mybatis and JDBC on Statement). StatementHandler is mainly used for: Create Statement object Bind ...

You can visit Code cloud - Leyou mall To get the engineering code of Leyou mall. You can visit Baidu cloud leyouyou mall Password: ppzy to get information about Leyou mall. 1, Create parent project Maven Project to manage dependencies     GroupId: the unique identifier in the project, which corresponds to the package structure in java. Her ...

Problem description @MapperScan annotation is generally configured to use dao or mapper's scanning package to operate the database, which is generally an interface. If there are other interfaces in dao layer, such as @ Service, an error will be reported Solution 1 Remove the service package. The met ...

The first time I wrote back-end, I went online to find many tutorials, but I didn't find many details. I found a lot of holes when I did it myself. I filled in the process of building the holes I met. As long as I followed the tutorial, you can build a complete ssm framework Title first create project ...

1. BeanFactoryPostProcessor interface Official website address: https://docs.spring.io/spring/docs/5.2.0.RELEASE/spring-framework-reference/core.html#beans-factory-extension-factory-postprocessors org.springframework.beans.factory.config.BeanFactoryPostProcessor. The semantics of this interface are s ...

1. Create a project environment Check Web, Mybatis, MySQL as follows Depends on the following <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>mysql&lt ...

There are two entities: user and membership card. A user can only process one membership card, that is, one-to-one.     user_tb: The primary key card_no of card_tb is introduced as the foreign key.     card_tb:         Mode 1: Use extension classes to implement one-to-one (1) Create a new User class under the pojo package: package com.chy.p ...