mybatisplus的querywarrper.eq怎么用
时间: 2024-05-08 14:18:02 浏览: 14
可以使用以下代码示例来使用mybatisplus的querywarrper.eq:
```
QueryWrapper<Entity> queryWrapper = new QueryWrapper<>();
queryWrapper.eq("column_name", value);
List<Entity> entityList = entityMapper.selectList(queryWrapper);
```
其中,column_name是需要查询的列名,value是需要匹配的值,Entity是实体类名,entityMapper是mybatisplus生成的mapper接口。使用eq可以根据指定列名和值来查找符合条件的记录。
相关问题
mybatisplus.eq
在使用Mybatis-Plus时,可以通过eq方法来进行等值查询。eq方法接受两个参数,第一个参数是实体类的字段,第二个参数是要查询的值。例如,使用eq方法进行等值查询可以按照以下方式进行操作:
LambdaQueryWrapper<TbCloudbox> lqDevice = new LambdaQueryWrapper<>();
lqDevice.eq(TbCloudbox::getStreetNumber, "1354322180948406274");
List<TbCloudbox> list = iTbCloudboxService.list(lqDevice);
在上述代码中,eq方法的第一个参数是TbCloudbox::getStreetNumber,表示要查询TbCloudbox实体类中的streetNumber字段,第二个参数是"1354322180948406274",表示要查询的值。通过这样的方式,可以方便地使用Wrapper的便利同时自定义SQL。[2][3]
mybatisplus. eq or and
MyBatis Plus provides two methods, `eq` and `and`, for constructing query conditions.
1. `eq`: The `eq` method is used to add an equal condition to the query. It takes two parameters: the column name and the value to compare. It generates a condition like "`column = value`". Here's an example:
```java
QueryWrapper<User> queryWrapper = new QueryWrapper<>();
queryWrapper.eq("age", 25);
```
2. `and`: The `and` method is used to add multiple conditions to the query. It takes a lambda function as a parameter, where you can specify multiple conditions using methods like `eq`, `like`, etc. It generates conditions combined with an "AND" operator. Here's an example:
```java
QueryWrapper<User> queryWrapper = new QueryWrapper<>();
queryWrapper.and(wrapper -> wrapper.eq("age", 25).like("name", "John"));
```
In the above example, it adds conditions like "`age = 25`" and "`name LIKE '%John%'`" using the `and` method.
These methods are part of MyBatis Plus's query wrapper (QueryWrapper) class, which makes it easier to construct complex queries without writing SQL statements explicitly.