mybatis plus or和and嵌套

MyBatis Plus provides support for both "OR" and "AND" nested conditions in query statements.

To use the "OR" nested condition, you can use the `or()` method provided by the `QueryWrapper` class. Here's an example:

QueryWrapper<User> queryWrapper = new QueryWrapper<>();
queryWrapper.eq("age", 20)
            .or()
            .eq("age", 30)
            .like("name", "John");
List<User> userList = userMapper.selectList(queryWrapper);

In this example, the generated SQL query will have a condition for `age = 20` OR `age = 30` AND `name` LIKE '%John%'.

To use the "AND" nested condition, you don't need any special method. You can simply chain multiple conditions using the `eq()`, `like()`, etc. methods provided by the `QueryWrapper` class. Here's an example:

QueryWrapper<User> queryWrapper = new QueryWrapper<>();
queryWrapper.eq("age", 20)
            .like("name", "John")
            .ge("salary", 5000);
List<User> userList = userMapper.selectList(queryWrapper);

In this example, the generated SQL query will have conditions for `age = 20` AND `name` LIKE '%John%' AND `salary` >= 5000.

You can mix "OR" and "AND" nested conditions as per your requirements to construct more complex queries in MyBatis Plus.