16 Jul

Unobvious "Unknown column in 'field list'" error

Recently we got request from our customer that something is going wrong with their database and they're are getting strange errors after each insert or update to specific table. The strangeness caused by "Unknown column 'column-name' in 'field list'" message while this column was existing in this table. Our investigation shown that this was caused by trigger on the table they were trying to do the insert/update. This trigger did the insert to another table where the mentioned column didn't exist. Let me show you example:

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31 Jan

WebScaleSQL builds for the MySQL Community

We have been looking at the WebScaleSQL project with great excitement. As with any new enhancements to the MySQL world, we need to test extensively to ensure we can give PSCE customers the best advice possible. Since this project is source only, we decided to add WebScaleSQL builds to our repo, so we could examine the changes being introduced by all the different collaborators.

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05 Apr

Lost connection to MySQL server during query

When an application runs a query in MySQL, from time to time, it may receive various errors. Some are related to syntax errors in the query text itself, some occur because the statement attempted an illegal operation such as for example writing a duplicate value into a column with unique constraint. But there are a few that are not as easy to figure out, because they have no direct relationship with the actual work being done. One of such error messages reads "Lost connection to MySQL server during query". What does it actually mean? If it appears frequently, how to diagnose what the problem may be?

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04 Apr

How to resize InnoDB logs?

If for any reason you need to change the size of InnoDB log files (also known as transaction logs), but not sure how to do it, this post will guide you through the steps.

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