在SQL中包含（插入）具有三个表的新行

Question

我遇到了一个问题：

我想在电视广告项目（P300）中加入Joy Davies，费用为800.

我需要在PALLOCATION表中更改此内容。

表名：EMPLOYEE

Emp_id | Emp_name          | Address            | Area of Expertise
==========================================================================
123456 | Kayleigh Donald   | 23 LakeAvenue      | Script writing
123457 | Fiaz Hussain      | 12 Riverside Drive | Production
123458 | Debbie Jackson    | 17 Long Road       | Design
123459 | Melissa Jefferies | 45 The High Street | Design
123460 | Nirmal Singh      | 34 East Street     | Script writing
123461 | Joy Davies        | 76 Broadway        | Storyboarding
123462 | Daniel Ortez      | 23 The Green       | Production

表名：PALLOCATION

Emp_id | PROJECT_ID | STAFF_COST
==============================================
123456 |    P300    | 900
123457 |    P300    | 1500
123456 |    D400    | 2000
123458 |    D400    | 400
123458 |    P200    | 350
123460 |    P200    | 800
123462 |    P200    | 400

表名：PROJECTS

PROJECT_ID | Project_name | Client
==============================================
  P300     | TV Ad        | GSK
  D400     | Billboard Ad | GSK 
  P200     | Radio Ad     | Prontaprint

我试图通过使用这个sql实现这一点。

INSERT INTO Pallocation (Emp_id, Project_id, Staff_cost)
VALUES ('123461', 'P300', '800')
FROM Pallocation JOIN Employee ON Emp_id E = Emp_id Pa 
    JOIN Project ON Project_id Pr = Project id Pa
    WHERE Emp_name...

我意识到这似乎是错的。请你指导我一下吗？

谢谢

Answer 1

您不需要FROM

标准插入语法是

INSERT INTO table_name
VALUES (value1,value2,value3,...);

所以你只需要：

INSERT INTO Pallocation (Emp_id, Project_id, Staff_cost) 
VALUES ('123461', 'P300', '800');

Answer 2

只检查空值以确保数据完整性

if (Request::isMethod('get'))
{
    //Here you can add your custom exception.
}