mybatisplus or拼接

MyBatis-Plus (also known as MyBatis++) is an enhanced wrapper library for MyBatis, which is a popular Java persistence framework. It provides additional features and simplifies the development process.

To perform OR conditions in MyBatis-Plus, you can use the `or` method provided by the QueryWrapper class. Here's an example:

QueryWrapper<User> queryWrapper = new QueryWrapper<>();
queryWrapper.eq("age", 25)
    .or()
    .eq("age", 30);
List<User> userList = userMapper.selectList(queryWrapper);

In this example, we create a `QueryWrapper` object and call the `eq` method to specify the conditions. The `or` method is used to perform an OR operation between the conditions. Finally, we execute the query using the `selectList` method.

This will generate a SQL query like: `SELECT * FROM user WHERE age = 25 OR age = 30;`

You can chain multiple `or` methods to perform more complex OR conditions. Additionally, MyBatis-Plus provides other methods like `or` and `orNew` to handle more advanced scenarios.