Tag: INDEX

Feed: Planet MySQL; Author: Monyog; Author: Robert AgarTuning database performance is a complicated task that can be a thorn in the side of the database team. There are many interconnected components and environmental aspects that come under consideration when attempting to optimize the performance of your database systems. A DBA can be hard-pressed to determine where to begin their optimization efforts. An initial investigation may concentrate on the network and hardware on which the database is running. These inquiries may uncover issues that can be easily identified and addressed. It may be a simple matter of adding some disk space ... Read More

Feed: Planet MySQL; Author: MySQL Performance Blog; Percona announces the release of Percona Server for MySQL 8.0.16-7 on August 15, 2019 (downloads are available here and from the Percona Software Repositories).This release is based on MySQL 8.0.16. It includes all bug fixes in these releases. Percona Server for MySQL 8.0.16-7 is now the current GA release in the 8.0 series. All of Percona’s software is open-source and free.Percona Server for MySQL 8.0.16 includes all the features available in MySQL 8.0.16 Community Edition in addition to enterprise-grade features developed by Percona. For a list of highlighted features from both MySQL 8.0 and Percona ... Read More

Feed: Recent Announcements. Oracle Database 18c introduces many new features such as Polymorphic Table Functions, Schema Only Accounts, Scalable Sequences, and others.  A Polymorphic Table Function (PTF) is a type of table function whose return type is determined by the arguments passed into the PTF. This is ideal for developers if they want to provide generic extensions that support arbitrary input tables or queries. You can create Schema Only Accounts, for object ownership without allowing clients to log in to the schema. Scalable Sequences reduce the sequence and index block contention and can improve the performance of concurrent data ingestion ... Read More

Feed: Planet MySQL; Author: Dave Stokes; Multi-Valued Indexes are going to change the way you think about using JSON data and the way you architect your data. Before MySQL 8.0.17 you could store data in JSON arrays but trying to search on that data in those embedded arrays was tricky and usually required a full table scan.  But now it is easy and very quick to search and to access the data in JSON arrays. Multi-Valued Indexes A Multi-Valued Index (MVI) is a secondary index defined on a column made up of an array of values.  We are all used ... Read More

Feed: Planet big data. Author: J.P. Gownder. So you’ve got a great new idea for how technology-driven innovations can transform your business, reinvent the way employees work, and/or drive customer obsession. That’s a great start! But too many of you tell us, “I’m really excited about this new idea, but I can’t get the internal buy-in that’s needed to fund the initiative.” Building a business case and influencing your peers is key to every technology initiative, so overcoming this obstacle is critical. One of our new reports can help. Duncan Jones and I coauthored a new version of the report, ... Read More

Feed: Planet MySQL; Author: Vlad Mihalcea; (Last Updated On: August 13, 2019) Introduction In this article, we are going to see how we can limit the SQL query result set to the Top-N rows only. Limiting the SQL result set is very important when the underlying query could end up fetching a very large number of records, which can have a significant impact on application performance. Why limit the number of rows of a SQL query? Fetching more data than necessary is the number one cause of data access performance issues. When a given business use case is developed, the ... Read More

Feed: R-bloggers. Author: insightr. [This article was first published on R – insightR, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. Introduction Today we are going to talk about quantile regression. When we use the lm command in R we are fitting a linear regression using Ordinary Least Squares (OLS), which has the interpretation of a model for the conditional mean of on . However, sometimes we may need to look at more ... Read More

Feed: Blue Medora. Author: Nate Coppinger.  Monitoring MongoDB Made easy Maintaining the health and performance of your IT infrastructure can be one of the biggest headaches you face in your time as an IT professional. With so many moving parts it can be nearly impossible to keep track of them all and how they interact with each other making it quite difficult to efficiently and successfully monitor MongoDB. One day you may log into your MongoDB environment and it’s not returning your queries, or you’re not getting the results you expected. Now you have to figure out why this is ... Read More

Feed: Planet PostgreSQL. The temporary tables are a useful concept present in most SGBDs, even though they often work differently. This blog describes the technical features for this kind of tables either in PostgreSQL (version 11) or Oracle (version 12c) databases with some specific examples. Although the purpose of these tables could be the same for all SGBD’s, their specifics, or the way of implementation and manipulation, are completely different. This feature could be used both by developers or database administrators to store intermediate results that will be needed for further processing in order to provide good performance metrics. Temporary ... Read More

Feed: R-bloggers. Author: Brian Callander. [This article was first published on Brian Callander, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. Fitting a full Bayesian model can be slow, especially with a large dataset. For example, it’d be great to analyse the climate crisis questions in the European Social Survey (ESS), which typically has around 45,000 respondents from around Europe on a range of socio-political questions. There are two main ways of parallelising ... Read More