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What is a join query in mysql? I believe many inexperienced people don't know what to do about it. Therefore, this paper summarizes the causes and solutions of the problem. Through this article, I hope you can solve this problem.

1. It is divided into implicit join query and display join query, which are distinguished by whether they contain the inner join keyword or not.

2. The data in the master table and slave table can be queried if they meet the connection conditions, but will not be queried if they do not meet the connection conditions.

Example

-- 2.1implicit internal connection method select * from t_category c, t_product p WHERE c.cid = p.CNO;-- query the information of all items under the category of mobile phone numbers and the classification information SELECT * FROM t_product tp INNER JOIN t_category tc ON tp.cno = tc.cid WHERE tc.cname = 'mobile phone numbers' SELECT * from t_category c INNER JOIN t_product p ON c.cid = p.cno after reading the above content, have you mastered what is the method of join query in mysql? If you want to learn more skills or want to know more about it, you are welcome to follow the industry information channel, thank you for reading!

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