Shulou(Shulou.com)05/31 Report--

MySQL how to use group by report this is incompatible with sql_mod, I believe that many inexperienced people are helpless about this, for this reason this article summarizes the causes of the problem and solutions, through this article I hope you can solve this problem.

Below is all the data for the employee table.

This is incompatible with sql_mode=only_full_group_by

Looking at the sql_model parameter found:

ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

ONLY_FULL_GROUP_BY option is enabled, then when using group by, you can only select the options after query group by, or use the aggregation function.

Query only the columns following group by:

Using aggregate functions:

Both methods are not recommended!!

Recommended solutions:

1. Temporary restart mysql will fail

set @@GLOBAL.sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

2. Modify/etc/my.cnf

[mysqld]

Add a line

sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

Restart MySQL to take effect.

Do you know how MySQL uses group by to say this is incompatible with sql_mod? If you still want to learn more skills or want to know more related content, welcome to pay attention to the industry information channel, thank you for reading!

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