Author - Corrado Pandiani

MySQL: Disk Space Exhaustion for Implicit Temporary Tables

Implicit Temporary Tables

I was recently faced with a real issue about completely exhausting the disk space on MySQL. This was a serious issue because of the continuous outages of the service, as the customer had to constantly restart the server and wait for the next outage.
What was happening? In this article, I’m going to explain it […]

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Solve Query Failures Regarding ONLY_FULL_GROUP_BY SQL Mode

Solve Query Failures SQL mode

“Hey, what’s going on with my applications? I installed a newer version of MySQL. I have queries that perfectly run with the older version and now I have a lot of errors.”
This is a question some customers have asked me after upgrading MySQL. In this article, we’ll see what one of the most frequent […]

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Using Partial and Sparse Indexes in MongoDB

MongoDb using partial sparse indexes

In this article I’m going to talk about partial and sparse indexes in MongoDB® and Percona Server for MongoDB®. I’ll show you how to use them, and look at cases where they can be helpful. Prior to discussing these indexes in MongoDB in detail, though, let’s talk about an issue on a relational database like […]

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MongoDB 4.0: Using ACID Multi-Document Transactions

mongodb 4.0 acid compliant transactions

MongoDB 4.0 is around, and there are a lot of new features and improvements. In this article we’re going to focus on the major feature which is, undoubtedly, the support for multi-document ACID transactions. This novelty for a NoSQL database could be seen as a way to get closer to the relational world. Well, […]

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MongoDB: Investigate Queries with explain() and Index Usage (part 2)

MongoDB explain() method optimization tool

This is the second part of a two parts series. In MongoDB: index usage and MongoDB explain() we introduced the main index types supported by MongoDB, and how to create and use them. In this second article, we are going to see some examples on how to use explain() method to investigate queries. Do […]

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