Shulou(Shulou.com)06/03 Report--

Editor to share with you what mysql one-to-many relationship means. I hope you will gain something after reading this article. Let's discuss it together.

1. One-to-many relationship means that one row of data of the master table can correspond to multiple rows of data of the slave table at the same time, and in turn, the multi-row data of the slave table points to the same row of data of the master table.

2. The application scenarios are classification table and commodity table, class table and student table, user table and order table, etc.

Example

-- create a classification table CREATE TABLE category (cid INT PRIMARY KEY AUTO_INCREMENT,cname VARCHAR (50)) -- create CREATE TABLE product (pid INT PRIMARY KEY AUTO_INCREMENT,pname VARCHAR (50), price DOUBLE,cid INT)-- add a foreign key alter table product add foreign key (cid) references category (cid) to the merchandise table. After reading this article, I believe you have a certain understanding of what "mysql one-to-many relationship means". If you want to know more about it, you are welcome to follow the industry information channel. Thank you for reading!

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