QueryWrapper中eq的用法案例

public ResponseResult bind(DriverCarBindingRelationship driverCarBindingRelationship){

        /*
        * 判断：在绑定司机和车辆关系之前，先判断一下二者之间是否已经绑定，如果已经绑定过，则不容许再绑定
        * */
        QueryWrapper<DriverCarBindingRelationship> queryWrapper = new QueryWrapper<>();     //查询包装器
        //多种条件情况下进行查询，以下三种情况必须满足
        queryWrapper.eq("driver_id",driverCarBindingRelationship.getDriverId());
        queryWrapper.eq("car_id",driverCarBindingRelationship.getCarId());
        queryWrapper.eq("bind_state",DriverCarConstants.DRIVER_CAR_BIND);
        Integer integer = driverCarBindingRelationshipMapper.selectCount(queryWrapper);
        if(integer.intValue()>0){
            return ResponseResult.fail(CommonStatusEnum.DRIVER_CAR_BIND_EXIST.getCode(),CommonStatusEnum.DRIVER_CAR_BIND_EXIST.getValue());
        }
}

底层运行结果：

Creating a new SqlSession
SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@66061384] was not registered for synchronization because synchronization is not active
JDBC Connection [HikariProxyConnection@704441103 wrapping com.mysql.cj.jdbc.ConnectionImpl@4e911e70] will not be managed by Spring

Preparing: SELECT COUNT( * ) FROM driver_car_binding_relationship WHERE (driver_id = ? AND car_id = ? AND bind_state = ?)
Parameters: 53(Long), 6(Long), 1(Integer)
< Columns: COUNT( * )
< Row: 0
<== Total: 1
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@66061384]