Home  >  Article  >  Database  >  Detailed information on rules and restrictions

Detailed information on rules and restrictions

巴扎黑
巴扎黑Original
2017-06-10 17:22:571554browse

View introduction requires MySQL 5 MySQL 5 adds support for views. Therefore, the contents of this chapter apply to MySQL 5 and later versions. Views are virtual tables. Unlike tables that contain data, views only contain queries that dynamically retrieve the data when used. The best way to understand the view is to look at an example: Input: select cust_name , cust_contact from customers, orders, orderitems where customers.cust_id = orders.cust_id and orderutems.order_num = order.orders.order_num and prod_id = 'TNT2'; this query Used to retrieve customers who have ordered a specific product. Anyone who needs this

1. Introduction to mysql views and why they are used and their rules and limitations

Detailed information on rules and restrictions

##Introduction: Requires MySQL 5 MySQL 5 adds support for views. Therefore, the contents of this chapter apply to MySQL 5 and later versions. Views are virtual tables. Unlike tables that contain data, views only contain queries that dynamically retrieve the data when used. The best way to understand views is to look at an example:

[Related Q&A recommendations]:

The above is the detailed content of Detailed information on rules and restrictions. For more information, please follow other related articles on the PHP Chinese website!

Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn