Fri, 16 Feb 2024 23:28:26 +0000 en-US hourly 1 https://wordpress.org/?v=6.5.2 https://www.percona.com/blog/wp-content/uploads/2023/02/cropped-percona-favicon-32x32.png 32 32 76301791 https://www.percona.com/blog/pros-and-cons-of-wildcard-indexes-on-mongodb/ https://www.percona.com/blog/pros-and-cons-of-wildcard-indexes-on-mongodb/#respond Fri, 22 Dec 2023 13:56:45 +0000 https://www.percona.com/blog/?p=92669 ​​MongoDB is a schemaless database that is extremely flexible. When you create a collection, you don’t have to specify a structure in advance, providing field names and data types. Just start inserting JSON documents, and MongoDB will store them, no matter which fields and data types you provide. As a consequence, a collection can store […]]]> https://www.percona.com/blog/pros-and-cons-of-wildcard-indexes-on-mongodb/feed/ 0 92669 https://www.percona.com/blog/invisibilities-in-mysql-8-0/ https://www.percona.com/blog/invisibilities-in-mysql-8-0/#comments Thu, 03 Aug 2023 12:30:10 +0000 https://www.percona.com/blog/?p=89751 In this article, I want to discuss a couple of pretty new features in MySQL 8.0 — and an older one. Maybe these are minor features you are not aware of, and maybe not so relevant, to be honest. But it is worth providing a quick overview, showing how they work, and how they could […]]]> https://www.percona.com/blog/invisibilities-in-mysql-8-0/feed/ 1 89751 https://www.percona.com/blog/want-mongodb-performance-you-will-need-to-add-and-remove-indexes/ https://www.percona.com/blog/want-mongodb-performance-you-will-need-to-add-and-remove-indexes/#comments Sat, 15 Jul 2023 13:43:18 +0000 https://www.percona.com/blog/?p=74884 This blog was originally published in March 2021 and was updated in July 2023.Good intentions can sometimes end up with bad results.  Adding indexes boosts performance until it doesn’t. Avoid over-indexing.The difference between your application being fast, responsive, and scaling properly depends on how you use indexes in the database. MongoDB is no different; its […]]]> https://www.percona.com/blog/want-mongodb-performance-you-will-need-to-add-and-remove-indexes/feed/ 3 74884 https://www.percona.com/blog/mysql-8-0-functional-indexes/ https://www.percona.com/blog/mysql-8-0-functional-indexes/#respond Sat, 15 Jul 2023 12:24:54 +0000 https://www.percona.com/blog/?p=79665 This blog was originally published in January 2022 and was updated in July 2023.Working with hundreds of different customers, I often face similar problems around running queries. One very common problem when trying to optimize a database environment is index usage. A query that cannot use an index is usually a long-running one, consuming more […]]]> https://www.percona.com/blog/mysql-8-0-functional-indexes/feed/ 0 79665 https://www.percona.com/blog/set-theory-in-mysql-8-0-union-and-now-intersect-and-except/ https://www.percona.com/blog/set-theory-in-mysql-8-0-union-and-now-intersect-and-except/#comments Wed, 02 Nov 2022 13:16:07 +0000 https://www.percona.com/blog/?p=83283 Are you familiar with the UNION statement for your SQL queries? Most likely, you are. It has been supported for a long time.In case you are not familiar with UNION, don’t worry, I’m going to show you how it works with simple examples.Considering “Set Theory”, other than the UNION, starting from the newly deployed MySQL […]]]> https://www.percona.com/blog/set-theory-in-mysql-8-0-union-and-now-intersect-and-except/feed/ 2 83283 https://www.percona.com/blog/window-functions-in-mysql-8-0/ https://www.percona.com/blog/window-functions-in-mysql-8-0/#comments Thu, 11 Aug 2022 12:06:26 +0000 https://www.percona.com/blog/?p=81575 I have recently written an article for this blog presenting Window Functions for MongoDB 5.0. I used some public Italian COVID-19 data for a few real examples. Please have a look at it if you like.Then I thought I should provide the same even for a relational database like MySQL.MySQL introduced Window Functions in version […]]]> https://www.percona.com/blog/window-functions-in-mysql-8-0/feed/ 1 81575 https://www.percona.com/blog/window-functions-in-mongodb-5-0/ https://www.percona.com/blog/window-functions-in-mongodb-5-0/#respond Wed, 29 Jun 2022 14:08:18 +0000 https://www.percona.com/blog/?p=81274 I have already presented in previous posts some of the new features available on MongoDB 5.0: resharding and time series collections. Please have a look if you missed them:MongoDB 5.0 Time Series CollectionsResharding in MongoDB 5.0In this article, I would like to present another new feature: window functions.Window functions are quite popular on relational databases, […]]]> https://www.percona.com/blog/window-functions-in-mongodb-5-0/feed/ 0 81274 https://www.percona.com/blog/mongodb-5-0-time-series-collections/ https://www.percona.com/blog/mongodb-5-0-time-series-collections/#respond Wed, 20 Oct 2021 14:31:00 +0000 https://www.percona.com/blog/?p=78683 In a previous article, I tested a new feature of MongoDB 5.0: resharding. Today, I take a look at another new feature: the Time Series collections.The Time Series collection is an astonishing new feature available in MongoDB 5.0. Based on the first tests I have done, the Time Series support provides comparable performance to the […]]]> https://www.percona.com/blog/mongodb-5-0-time-series-collections/feed/ 0 78683 https://www.percona.com/blog/resharding-in-mongodb-5-0/ https://www.percona.com/blog/resharding-in-mongodb-5-0/#respond Tue, 24 Aug 2021 13:55:05 +0000 https://www.percona.com/blog/?p=77591 MongoDB 5.0 has been released with a bunch of new features. An important one is the capability to completely redefine the shard key of a collection in a sharded cluster. Resharding was a feature frequently requested by the customers. In MongoDB 4.4 only the refining of the shard was available; from now on you can […]]]> https://www.percona.com/blog/resharding-in-mongodb-5-0/feed/ 0 77591 https://www.percona.com/blog/mongodb-tuning-anti-patterns-how-tuning-memory-can-make-things-much-worse/ https://www.percona.com/blog/mongodb-tuning-anti-patterns-how-tuning-memory-can-make-things-much-worse/#comments Mon, 24 May 2021 14:50:21 +0000 https://www.percona.com/blog/?p=75633 It’s your busiest day of the year and the website has crawled to a halt and finally crashed… and it was all because you did not understand how MongoDB uses memory and left your system open to cluster instability, poor performance, and unpredictable behavior. Understanding how MongoDB uses memory and planning for its use can […]]]> https://www.percona.com/blog/mongodb-tuning-anti-patterns-how-tuning-memory-can-make-things-much-worse/feed/ 1 75633 https://www.percona.com/blog/thinking-about-deploying-mongodb-read-this-first/ Thu, 14 Jan 2021 17:55:05 +0000 https://www.percona.com/blog/?p=73468 Are you thinking about deploying MongoDB? Is it the right choice for you?Choosing a database is an important step when designing an application. A wrong choice can have a negative impact on your organization in terms of development and maintenance. Also, the wrong choice can lead to poor performance.Generally speaking, any kind of database can […]]]> 73468 https://www.percona.com/blog/enabling-https-connections-to-percona-monitoring-and-management-using-custom-certificates/ Wed, 09 Dec 2020 15:09:09 +0000 https://www.percona.com/blog/?p=72846 Whichever way you installed Percona Monitoring and Management 2 (PMM2), using the docker image or an OVF image for your supported virtualized environment, PMM2 enables, by default, two ports for the web connections: 80 for HTTP and 443 for HTTPS. Using HTTPS certificates are requested for encrypting the connection for better security.All the installation images […]]]> 72846 https://www.percona.com/blog/new-in-mongodb-4-4-hidden-index/ Thu, 05 Nov 2020 17:04:58 +0000 https://www.percona.com/blog/?p=72401 We already presented a previous article on the index types available on MongoDB. MongoDB 4.4 was released a few months ago and introduced a new interesting feature: the hidden index.This feature is also available on Percona Server for MongoDB 4.4. In this article, we’ll see what it is.What is a Hidden IndexA hidden index is […]]]> 72401 https://www.percona.com/blog/mongodb-utilization-of-an-index-on-subdocuments/ Fri, 24 Jul 2020 14:14:31 +0000 https://www.percona.com/blog/?p=69770 MongoDB has a lot of possibilities for creating indexes. We have seen in previous articles some of the available index types and discussed explain() usage:Using Partial and Sparse Indexes in MongoDBMongoDB Index Types and MongoDB explain() (part 1)MongoDB: Investigate Queries with explain() and Index Usage (part 2)You can have a look at those if you […]]]> 69770 https://www.percona.com/blog/real-time-replication-from-dynamodb-to-mongodb/ Wed, 20 May 2020 15:12:29 +0000 https://www.percona.com/blog/?p=67637 Recently I’ve been faced with an interesting challenge. How can I replicate data, in real-time, from DynamoDB to MongoDB?Why would I need real-time replication like that? For example: Running on MongoDB different queries relying on different indexes Having on MongoDB more fields or converted fields (you can do it during the replication) so you can […]]]> 67637 https://www.percona.com/blog/introduction-to-mysql-8-0-recursive-common-table-expression-part-2/ https://www.percona.com/blog/introduction-to-mysql-8-0-recursive-common-table-expression-part-2/#comments Thu, 13 Feb 2020 17:12:08 +0000 https://www.percona.com/blog/?p=65150 This is the second part of a two-articles series. In the first part, we introduced the Common Table Expression (CTE), a new feature available on MySQL 8.0 as well as Percona Server for MySQL 8.0. In this article, we’ll present the Recursive Common Table Expression. SQL is generally poor at recursive structures, but it is […]]]> https://www.percona.com/blog/introduction-to-mysql-8-0-recursive-common-table-expression-part-2/feed/ 7 65150 https://www.percona.com/blog/introduction-to-mysql-8-0-common-table-expressions-part-1/ https://www.percona.com/blog/introduction-to-mysql-8-0-common-table-expressions-part-1/#comments Mon, 10 Feb 2020 16:09:22 +0000 https://www.percona.com/blog/?p=65069 This blog is the first part of a two-articles series. In this article, I’m going to introduce the Common Table Expression (CTE), a new feature available on MySQL 8.0, as well as Percona Server for MySQL 8.What is a Common Table Expression?We can define a CTE as an alternative to a derived table. In a […]]]> https://www.percona.com/blog/introduction-to-mysql-8-0-common-table-expressions-part-1/feed/ 4 65069 https://www.percona.com/blog/percona-backup-for-mongodb-in-action/ https://www.percona.com/blog/percona-backup-for-mongodb-in-action/#comments Tue, 17 Dec 2019 16:01:10 +0000 https://www.percona.com/blog/?p=62505 We recently released Percona Backup for MongoDB(PBM) as GA. It’s our open source tool for taking a consistent backup of a running standalone mongod instance, a Replica Set, or a Sharded Cluster as well. The following articles can give you an overview of the tool: Avoid Vendor Lock-in with Percona Backup for MongoDB Percona Backup […]]]> https://www.percona.com/blog/percona-backup-for-mongodb-in-action/feed/ 6 62505 https://www.percona.com/blog/column-histograms-on-percona-server-and-mysql-8-0/ Tue, 29 Oct 2019 14:24:10 +0000 https://www.percona.com/blog/?p=62748 From time to time you may have experienced that MySQL was not able to find the best execution plan for a query. You felt the query should have been faster. You felt that something didn’t work, but you didn’t realize exactly what.Maybe some of you did tests and discovered there was a better execution plan […]]]> 62748 https://www.percona.com/blog/mongodb-impact-free-index-builds-using-detached-replicaset-nodes/ https://www.percona.com/blog/mongodb-impact-free-index-builds-using-detached-replicaset-nodes/#comments Mon, 05 Aug 2019 15:01:27 +0000 https://www.percona.com/blog/?p=58979 Creating an index on a MongoDB collection is simple; just run the command CreateIndex and that’s all there is to it. There are several index types available, and in a previous post, you can find the more important index types: MongoDB index types and explain().The command is quite simple, but for MongoDB, building an index […]]]> https://www.percona.com/blog/mongodb-impact-free-index-builds-using-detached-replicaset-nodes/feed/ 3 58979