加入多個表格並創建一個表格

Question

我有3張名爲Advance，Transport和Medicine的表格。我想加入這三個表，並拿出一個像emp_id 1的最後一個表。是否有可能使用dql（doctrine）或sql在sql級別執行此操作？

Answer 1

CREATE TABLE NewTable 
SELECT Date, 
     Emp_ID, 
     Amount As Advance, 
     NULL AS Transport, 
     NULL AS Medicine 
FROM Advance 
WHERE Emp_ID = 1   -- remove this WHERE clause to include all emp_ID 
UNION ALL 
SELECT Date, 
     Emp_ID, 
     NULL As Advance, 
     Amount AS Transport, 
     NULL AS Medicine 
FROM Transport 
WHERE Emp_ID = 1   -- remove this WHERE clause to include all emp_ID 
UNION ALL 
SELECT Date, 
     Emp_ID, 
     NULL As Advance, 
     NULL AS Transport, 
     Amount AS Medicine 
FROM Medicine 
WHERE Emp_ID = 1   -- remove this WHERE clause to include all emp_ID 

• CREATE TABLE...SELECT Syntax

您還可以創建在這個VIEW，

CREATE VIEW EmployeeView 
AS 
SELECT Date, 
     Emp_ID, 
     Amount As Advance, 
     NULL AS Transport, 
     NULL AS Medicine 
FROM Advance 
WHERE Emp_ID = 1   -- remove this WHERE clause to include all emp_ID 
UNION ALL 
SELECT Date, 
     Emp_ID, 
     NULL As Advance, 
     Amount AS Transport, 
     NULL AS Medicine 
FROM Transport 
WHERE Emp_ID = 1   -- remove this WHERE clause to include all emp_ID 
UNION ALL 
SELECT Date, 
     Emp_ID, 
     NULL As Advance, 
     NULL AS Transport, 
     Amount AS Medicine 
FROM Medicine 
WHERE Emp_ID = 1   -- remove this WHERE clause to include all emp_ID 

• CREATE VIEW Syntax