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MySQL: who’s filling my error log?

This morning, a user asked in the MySQL Community Slack if somebody had an idea why the error log was filled up continuously with a warning messages like this one: 2020-07-24T06:54:00.877128Z 46 [Warning] [MY-013360] [Server] Plugin sha256_password reported: ”sha256_password’ is deprecated and will be removed in a future release. Please use caching_sha2_password instead’ The context was that the user upgraded … Read More

MySQL – Keep an eye on your auto_increment values

In MySQL, it’s very common and recommended to you an auto_increment as Primary Key. However that integer can have different types each having their size limitation, and they can also be signed or not. Many people when creating a table use by default the following syntax do define their auto_increment primary key: id int auto_increment primary key This is a … Read More

MySQL & InnoDB Disk Space

Yesterday, Bhuvanesh published an article about how to verify the difference between allocated diskspace for a tablespace and the the data in it. I commented with an old post explaining how to get some similar info only using SQL in case you don’t have filesystem access. And finally, my friend Bill Karwin, commented how this info is not always accurate. … Read More

MySQL: CPU information from SQL

Do you know that it’s possible to get information from the CPUs of your MySQL Server from SQL ? If you enable the status for the ┬áINNODB_METRICS table in INFORMATION_SCHEMA, you will be able to query CPU information.

How to grant privileges to users in MySQL 8.0

It seems, that this is a question that regularly shows up in forums or stackoverflow. To start, let’s highlight the fact that in MySQL 8.0 it’s not any more possible to create a user directly from the GRANT command (ERROR 1410 (42000): You are not allowed to create a user with GRANT). This means that to grant some privileges, the … Read More