Indexing plays a quintessential role in database query performance and MongoDB is no exception. Choosing the best index for a query will improve its performance, while a bad one could lead to huge execution times and high memory utilization. In…

Recently a client came to me asking “How do we verify if a full text search index is being used on MongoDB?” The db.showIndexes() command shows an index on a text field, but explain() shows COLLSCAN and the query is…

In this blog post, I’ll walk you through setting up encrypted replication on MySQL 5.7 with GTID enabled. I will walk you through how to create sample certificates and keys, and then configure MySQL to only use replication via an…

Consider the following situation: You have a data ingestion pipeline where the data comes in real-time on weekdays and is stored in a dated folder.  The day’s data needs to be ingested within four hours. An instant response may be…

A client recently asked us to migrate a Cassandra cluster running in Docker containers to Elassandra, with the data directory persisted via a bind mount. Elassandra is a fork of Cassandra integrated closely with Elasticsearch, to allow for a highly scalable…

One problem that’s a lot less common these days is swapping. Most of the issues that cause swapping with MySQL have been nailed down to several different key configuration points, either in the OS or MySQL, or issues like the…

I’ve been posting quite a bit about Docker as I’ve been working with it a lot as of late. I thought I would share something interesting I discovered a couple weeks ago while working on setting up a Docker container-based…

Orchestrator is datacenter-aware, meaning that it takes nodes location into consideration when performing a topology change. Let’s explore the options to make Orchestrator automatically detect this configuration.   Using MySQL server One option is to use the monitored database server…

In one of the projects I have been working on, one requirement was the ability to stop traffic from reaching a MySQL host which has been lagging behind its master for longer than a specific amount of time and then…

Cassandra nodetool provides several types of commands to manage your Cassandra cluster. See my previous posts for an orientation to Cassandra nodetool and using nodetool to get Cassandra information. My colleague has provided an in-depth analysis of backup strategies in…