查询：如何选择特定列

Question

我正在使用Spring数据jpa来创建服务。使用查询，我从多个表中提取记录。我在模型类中使用了映射。房间部门映射模型类与部门和房间进行映射。房间与建筑相符。

我只想从建筑中选择建筑名称。

谁能告诉我怎么办？

查询DSL

query.select(Projections.bean(RoomDepartmentMapping.class,roomDepartmentMapping.nRoomAllocationId,roomDepartmentMapping.sStatus,
        Projections.bean(Department.class,department.nDeptId,department.sClientDeptId,department.sDeptName).as("department"),
        Projections.bean(Room.class,room.nRoomId,room.sFloor,room.sRoomNumber,room.nBuildId,room.nCampusId,room.building).as("room")))           
             .from(roomDepartmentMapping);

结果

[
  {
    "nRoomAllocationId": 1,
    "sStatus": "A",
    "department": {
      "nDeptId": 21920,
      "sDeptName": "Unassignable Space",
      "sClientDeptId": "BBBBBB"
    },
    "room": {
      "nRoomId": 883886,
      "nCampusId": 231,
      "nBuildId": 9713,
      "sFloor": "9",
      "sRoomNumber": "914",
      "building": {
        "nBuildingId": 9713,
        "sBuildName": "Bronk Laboratory",
        "sClientBuildId": "406",
        "nBuildingInstId": 60,
        "nTempBuildingId": 2,
        "nNoOfFloors": 0
      },
      "nroomId": 883886
    }
  },
...
...
]

Answer 1

QueryDsl似乎没有提供自定义要显示的字段的方法，选择是使用jackson的@JsonProperty（serialized=false），它将隐藏不想在json字符串中显示的属性。