Author - David Ducos

Finding Table Differences on Nullable Columns Using MySQL Generated Columns

MySQL generated columns

Some time ago, a customer had a performance issue with an internal process. He was comparing, finding, and reporting the rows that were different between two tables. This is simple if you use a LEFT JOIN and an 
IS NULL  comparison over the second table in the WHERE clause, but what if the column could be […]

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InnoDB Buffer Pool Resizing: Chunk Change

InnoDB Buffer Pool

Since MySQL 5.7.5, we have been able to resize dynamically the InnoDB Buffer Pool. This new feature also introduced a new variable — innodb_buffer_pool_chunk_size — which defines the chunk size by which the buffer pool is enlarged or reduced. This variable is not dynamic and if it is incorrectly configured, could lead to undesired […]

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Using Hints to Analyze Queries

Hints to Analyze Queries

In this blog post, we’ll look at using hints to analyze queries.
There are a lot of things that you can do wrong when writing a query, which means that there a lot of things that you can do to make it better. From my personal experience there are two things you should review first:

The table join […]

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Generated Columns and ProxySQL Instead of Referenced Tables

Generated Columns

In this post, we’ll look at how to improve queries using generated columns and ProxySQL instead of implementing a referenced table.
Developers and architects don’t always have the time or complete information to properly analyze and design a database. That is why we see tables with more fields than needed, or with incorrect types. The […]

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