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The content of this article mainly focuses on the example analysis of the changes of GROUP BY in MySQL8.0. The content of the article is clear and clear. It is very suitable for beginners to learn and is worth reading. Interested friends can follow the editor to read together. I hope you can get something through this article!

As shown in the question, MySQL 8.0 starts group by without sorting by default, so it is possible that the results will be different before MySQL 8.0 and 8.0, so we need to be vigilant.

Run the following SQL:

The following is version 8.0:

Run the same SQL:

If this is the case, paging is performed.

Version 5.7:

Version 8.0:

As can be seen from the above, the two results are different. The reason is that before 8.0, group by contains using filesort, while 8.0 does not. In order to avoid this problem, we must use order by for related sorting except for the optimization idea of index replacement sorting.

Thank you for your reading. I believe you have some understanding of the "sample Analysis of GROUP BY changes in MySQL8.0". Go ahead and practice it. If you want to know more about it, you can follow the website! The editor will continue to bring you better articles!

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