Question

是否可以在单个表上执行该查询？

我已经读过它可以由多个表完成（通过从第二个表中选择特定值来插入第一个表）

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

Answer 1

是否可以在单个表上执行该查询？

是的，有可能：

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;

的 LiveDemo

请注意，Table Spool
需要{{1}}
Halloween Effect

SQL：如何在具有特定id的特定列中插入数据

1 个答案: