SQL INSERT INTO SELECT 语句
本章节讲解 SQL INSERT INTO SELECT
语句
SQL INSERT INTO SELECT 语句
INSERT INTO SELECT
语句从一个表复制数据并将其插入另一个表中。
INSERT INTO SELECT
语句要求源表和目标表中的数据类型匹配。
注意: 目标表中的现有记录不受影响。
INSERT INTO SELECT 语法
将所有列从一个表复制到另一个表:
INSERT INTO table2
SELECT * FROM table1
WHERE condition ;
仅将一个表中的某些列复制到另一个表中:
INSERT INTO table2 ( column1 , column2 , column3 , ...)
SELECT column1 , column2 , column3 , ...
FROM table1
WHERE condition ;
Demo 数据库
在本教程中,我们将使用著名的 Northwind 示例数据库。
下是从 "Customers" 表中选择的内容:
CustomerID | CustomerName | ContactName | Address | City | PostalCode | Country |
---|---|---|---|---|---|---|
1 | Alfreds Futterkiste | Maria Anders | Obere Str. 57 | Berlin | 12209 | Germany |
2 | Ana Trujillo Emparedados y helados | Ana Trujillo | Avda。 de la Constitución 2222 | México D.F. | 05021 | Mexico |
3 | Antonio Moreno Taquería | Antonio Moreno | Mataderos 2312 | México D.F. | 05023 | Mexico |
以及从 "Suppliers" 表中选择:
SupplierID | SupplierName | ContactName | Address | City | Postal Code | Country |
---|---|---|---|---|---|---|
1 | Exotic Liquid | Charlotte Cooper | 49 Gilbert St. | Londona | EC1 4SD | UK |
2 | New Orleans Cajun Delights | Shelley Burke | P.O. Box 78934 | New Orleans | 70117 | USA |
3 | Grandma Kelly's Homestead | Regina Murphy | 707 Oxford Rd. | Ann Arbor | 48104 | USA |
SQL INSERT INTO SELECT 实例
以下 SQL 语句将 "Suppliers" 复制到 "Customers" 表中(未填充数据的列将包含 NULL):
实例
INSERT INTO Customers (CustomerName, City, Country)
SELECT SupplierName, City, Country FROM Suppliers;
以下 SQL 语句将 "Suppliers" 复制到 "Customers" 表中(填写所有列):
实例
INSERT INTO Customers (CustomerName, ContactName, Address, City, PostalCode, Country)
SELECT SupplierName, ContactName, Address, City, PostalCode, Country FROM Suppliers;
以下 SQL 语句仅将德国供应商(Supplier)复制到 "Customers" 表中:
实例
INSERT INTO Customers (CustomerName, City, Country)
SELECT SupplierName, City, Country FROM Suppliers
WHERE Country='Germany';