Tag: column

Feed: Planet MySQL; Author: Jesper Krogh; The other day, I was reading a blog by Magnus Hagander about tracking foreign keys throughout a schema in PostgreSQL. I thought it was a good idea, so I decided to look at how you can track foreign key in MySQL. The way I decided to do it was to start out with a table, then find all tables referencing the table by a foreign key. From this basic (and simple as it will be shown) query, it is possible to create a chain of relations. The key table for the queries is information_schema.KEY_COLUMN_USAGE ... Read More

Feed: Planet MySQL; Author: Dave Stokes; JSON has proven to be a very import data format with immense popularity. A good part of my time for the last two or so years has been dedicated to this area and I even wrote a book on the subject.  This is a comparison of the implementations of handling JSON data in MySQL and MariaDB. I had requests from the community and customers for this evaluation. JSON Data Types Are Not All Equal MySQL added a JSON data type in version 5.7 and it has proven to be very popular.  MariaDB has  JSON ... Read More

Feed: Blog. Author: CraigSMullins; Application developers must code efficient SQL and understand how to optimize SQL in order to develop efficient applications. But it is not just the programmer, but also the DBA who must understand SQL optimization. It is a joint responsibility and frequently requires robust tools to help code, modify, and optimize SQL effectively.The relational optimizer is at the heart of the DBMS. It is an inference engine responsible for determining the best possible database navigation strategy for any given SQL request. The developer specifies what data is needed by coding the SQL statements, the DBMS accesses metadata ... Read More

Feed: SAS Blogs. Author: Sanjay Matange. Previously, I have written articles on how we could display more subject response data along with the traditional WaterFall graph showing the best  "Change from Baseline".  This is in response to the desire to see data like treatment duration for each subject in the same graph.  Otherwise, investigators have to view different graphs to see all the data, some of which may be sorted in different ways. One popular proposal is to display the best "Change from Baseline" along the front face of a 3D graph, with "Duration of Treatment" for each subject displayed ... Read More

Feed: Planet MySQL; Author: MySQL Performance Blog; PREVIOUS POST Percona announces the release of Percona Server for MySQL 5.7.23-24 on November 12, 2018 (downloads are available here and from the Percona Software Repositories). This release merges changes of MySQL 5.7.23, including all the bug fixes in it. Percona Server for MySQL 5.7.23-24 is now the current GA release in the 5.7 series. All of Percona’s software is open-source and free. This release introduces InnoDB encryption improvements and merges upstream MyRocks changes. Also, we’ve improved the usage of column families in MyRocks. The InnoDB encryption improvements are in Alpha quality and we don’t recommend ... Read More

Feed: Planet MySQL; Author: Sugu Sougoumarane; We continue the digest from the Slack discussions for Sep 22 2018 to Oct 5 2018. We've fallen slightly behind on this, but will catch up again soon. Enable VtGateExecute in vtctld Arsalan [Sep 22nd] Hi, I want to query vitess on vtgate but I have below error. How can i fix this problem? vitess@vtctldv3-hrl74:/$ vtctlclient -server 10.5.61.20:16999  VtGateExecute -server 10.5.61.21:16991 "show tables" E0923 05:14:55.169771    1102 main.go:61] Remote error: rpc error: code = Unknown desc = query commands are disabled (set the -enable_queries flag to enable) sougou you need to add this flag ... Read More

Feed: Cloudwards. Author: David Schmidt; Facebook has problems protecting your information. In a year full of concerning reports on how the social media platform polices — or fails to — users’ data, not only is it operating in an unflattering spotlight, but it’s also forcing some to consider their security. To help those people, we’ve put together this guide to Facebook privacy settings. When Facebook users answered questions about their personalities in a seemingly harmless survey in 2014, they never imagined a political firm involved in the 2016 U.S. presidential election was behind it. Even though only 270,000 survey takers ... Read More

Feed: Planet PostgreSQL. Here is a series of articles that will focus on a new feature in version 11. During the development of this version, a feature caught my attention. It can be found in releases notes : https://www.postgresql.org/docs/11/static/release-11.html Allow heap-only-tuple (HOT) updates for expression indexes when the values of the expressions are unchanged (Konstantin Knizhnik) I admit that this is not very explicit and this feature requires some knowledge about how postgres works, that I will try to explain through several articles: How MVCC works and heap-only-tuples updates When postgres do not use heap-only-tuple updates and introduction to the ... Read More

Feed: R-bloggers. Author: Econometrics and Free Software. Link to webscraping the data Link to Analysis, part 1 Introduction This is the third blog post that deals with data from the game NetHack, and oh boy, did a lot ofthings happen since the last blog post! Here’s a short timeline of the events: I scraped data from alt.org/nethack and made a package with the data available on Github(that package was too big for CRAN) Then, I analyzed the data, focusing on what monsters kill the players the most, and also whereplayers die the most @GridSageGames, developer of the roguelike Cogmind and ... Read More

Feed: Microsoft Azure Blog. Author: Estienne Granet. The SQL Security team is pleased to share the public preview release of Static Data Masking. Static Data Masking is a data protection feature that helps users sanitize sensitive data in a copy of their SQL databases.   Use cases Static Data Masking is designed to help organizations create a sanitized copy of their databases where all sensitive information has been altered in a way that makes the copy sharable with non-production users. Static Data Masking can be used for: Development and testing Analytics and business reporting Troubleshooting Sharing the database with a ... Read More