主键

简介

检验请求参数具有唯一性，例如商品表中的商品编号是唯一的，用户表中的邮箱是唯一的。

示例

准备数据表

假设有hrm.salaries 人力资源系统 - 员工的薪水信息表，结构如下：

--薪资表
CREATE TABLE `salaries` (
  `emp_no` int(11) NOT NULL,
  `salary` int(11) NOT NULL,
  `from_date` date NOT NULL,
  `to_date` date NOT NULL,
  PRIMARY KEY (`emp_no`,`from_date`),
  CONSTRAINT `salaries_ibfk_1` FOREIGN KEY (`emp_no`) REFERENCES `employees` (`emp_no`) ON DELETE CASCADE
)

通过上述表结构可以看到：

• 主键是『员工编号』emp_no和『开始日期』from_date的组合，用于唯一标识一条工资记录，值必须是唯一的
• 工号字段emp_no作为外键，外键约束参考外键

示例1：正常请求

POST http://127.0.0.1:21000
Content-Type: application/json;charset=utf-8

{
  "jsonrpc": "2.0",
  "method": "hrm.salaries.add",
  "params": {
    "empNo": 10010,
    "salary": 10000,
    "fromDate": "2023-10-01",
    "toDate": "2023-10-31"
  },
  "id": "client-unique-request-id"
}

响应

HTTP/1.1 200 OK
Content-Type: application/json; charset=utf-8

{
  "jsonrpc": "2.0",
  "result": {
    "empNo": 10010,
    "fromDate": "2023-10-01"
  },
  "id": "client-unique-request-id"
}

示例2：错误请求

重复提交该请求，检测到『员工编号』和『开始日期』的组合已经存在，响应错误。

POST http://127.0.0.1:21000
Content-Type: application/json;charset=utf-8

{
  "jsonrpc": "2.0",
  "method": "hrm.salaries.add",
  "params": {
    "empNo": 10010,
    "salary": 10000,
    "fromDate": "2023-10-01",
    "toDate": "2023-10-31"
  },
  "id": "client-unique-request-id"
}

响应错误

HTTP/1.1 400 Bad Request
Content-Type: application/json; charset=utf-8

{
  "jsonrpc": "2.0",
  "error": {
    "code": -32600,
    "message": "checking for primary key conflicts: duplicate primary key in hrm.salaries [empNo fromDate]",
    "data": {
      "errorCode": "EU.Constraint.PK.Duplicated",
      "errorDetails": [
        {
          "constraint": "PrimaryKeyDuplicated",
          "field": [
            "empNo",
            "fromDate"
          ],
          "fieldValue": [
            10010,
            "2023-10-01"
          ],
          "location": "hrm.salaries",
          "message": "duplicate primary key in hrm.salaries.[empNo fromDate] [10010 2023-10-01]"
        }
      ],
      "errorMessage": "duplicate primary key in hrm.salaries [empNo fromDate]"
    }
  },
  "id": "client-unique-request-id"
}

Tested on Luwak 1.13.0