SQL：如何使用特定的ID插入特定列中的數據

Question

是否可以在單個表上執行那種查詢？

我已閱讀，它可以由多個表來完成（在第一個表中插入通過選擇第二特定值）

INSERT INTO Customers (CustomerName, Country) 
SELECT SupplierName, Country FROM Suppliers 
WHERE Country='Germany'; 

Answer 1

是否有可能在單表查詢的執行樣？

是的，這是可能的：

CREATE TABLE Customers(ID INT IDENTITY(1,1), 
         CustomerName VARCHAR(100), Country VARCHAR(100)); 

INSERT INTO Customers (CustomerName, Country) 
VALUES ('John', 'USA'), ('Martin','Germany'); 

INSERT INTO Customers (CustomerName, Country) 
SELECT CustomerName, Country 
FROM Customers 
WHERE Country='Germany'; 

SELECT * 
FROM Customers; 

LiveDemo

記住Table Spool需要避免Halloween Effect