Tag: INDEX

Feed: Planet MySQL; Author: Valeriy Kravchuk; From the lack of comments to my previous post it seems everything is clear with ERROR 1213 in different kinds and forks of MySQL. I may still write a post of two about MyRocks or TokuDB deadlocks one day, but let's get back to my main topic of MySQL bugs. Today I continue my series of posts about community bug reports I am subscribed to with a review of bugs reported in November, 2018, starting from the oldest and skipping those MySQL 8 regression ones I've already commented on. I also skip documentation bugs ... Read More

Feed: R-bloggers. Author: Tinniam V Ganesh. The second edition of my book ‘Deep Learning from first principles:Second Edition- In vectorized Python, R and Octave’, is now available on Amazon, in both paperback ($14.99)  and kindle ($9.99/Rs449/-)  versions. Since this book is almost 70% code, all functions, and code snippets have been formatted to use the fixed-width font ‘Lucida Console’. In addition line numbers have been added to all code snippets. This makes the code more organized and much more readable. I have also fixed typos in the book The book includes the following chapters Table of Contents Preface 4 Introduction 6 ... Read More

Feed: Planet MySQL; Author: MC Brown; Clickhouse is a relatively new analytics and datawarehouse engine that provides for very quick insertion and analysing of data. Like most analytics platforms it’s built on a column-oriented storage basis and unlike many alternatives is completely open source. It’s also exceedingly fast, even on relatively modest platforms.Clickhouse does have some differences from some other environments, for example, data inserted cannot easily be updated, and it supports a number of different storage and table engine formats that are used to store and index the information. So how do we get into that from our MySQL transactional ... Read More

Feed: Redis Labs. Author: Dave Provenza. We are happy to announce the launch of Redis Enterprise 5.4, the latest version of our high performance, in-memory database platform. The new version contains the following major enhancements: Redis 5.0 GA — Redis Streams Redis Streams, introduced  in Redis 5.0, is one of the most popular products today in the Redis ecosystem. Redis Streams is a new data type that models a log data structure in-memory and implements additional powerful operations, such as: A set of blocking operations allowing consumers to wait for new data added to a stream by producers. A concept ... Read More

Feed: Planet MySQL; Author: FromDual; As we already stated in earlier articles in this blog [ and ] it is a good idea to use NULL values properly in MariaDB and MySQL.One of my Mantras in MariaDB performance tuning is: Smaller tables lead to faster queries! One consequence out of this is to store NULL values instead of some dummy values into the columns if the value is not known (NULL: undefined/unknown). To show how this helps related to space used by a table we created a little example: CREATE TABLE big_null1 ( id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY ... Read More

Feed: R-bloggers. Author: HighlandR. Are multiple births on the increase? My twin boys turned 5 years old today. Wow, time flies. Life is never dull, because twins are still seen as something of a novelty, so wherever we go, we find ourselves in conversation with strangers, who are intrigued by the whole thing. In order to save time if we ever meet, here’s some FAQ’s: No, they’re not identical Yes, I’m sure No, they do not have similar personalities They like different things – One likes Hulk and Gekko, the other likes Iron Man and Catboy. Recently I’ve been hearing ... Read More

Feed: Planet PostgreSQL. PREVIOUS POST PostgreSQL streaming physical replication with slots simplifies setup and maintenance procedures. Usually, you should estimate disk usage for the Write Ahead Log (WAL) and provide appropriate limitation to the number of segments and setup of the WAL archive procedure. In this article, you will see how to use replication with slots and understand what problems it could solve. Introduction PostgreSQL physical replication is based on WAL. Th Write Ahead Log contains all database changes, saved in 16MB segment files. Normally postgres tries to keep segments between checkpoints. So with default settings, just 1GB of WAL segment files is ... Read More

Feed: Puppet Blog Feed. Author: Dimitri Tischenko; Due to its declarative DSL and resource abstraction, Puppet is an excellent solution for enforcing compliance across any server estate. There are modules on the forge providing automatic hardening. Other modules make it easy to enforce best practices in middleware configurations. Configuration drift is reported as corrective changes to Puppet Enterprise Console. The world is a happy place.More and more organisations are required to scan their infrastructure and determine whether it complies with standardized security and hardening benchmarks, such as CIS, NIST, PCI or BSI (see links at end of article for more ... Read More

Feed: AWS Big Data Blog. re:Invent 2018 is around the corner! This year, data and analytics tracks are bigger than ever.This blog post highlights the data and analytics sessions at re:Invent 2018. If you’re attending this year, you want to check out the sessions, workshops, chalk talks, and builder sessions that we have at the conference. As in previous years, you can find these events in various topic categories, such as Analytics, Deep Learning, AI Summit, Serverless, Architecture, and Databases. We have great sessions from Intuit, Nike, Intel, WuXi NextCODE, Warner Brothers, AutoDesk, NFL, SendGrid, McDonald, AirBnB, Hilton, Guardian Life, ... Read More

Feed: Databasejournal.com - Feature Database Articles. Author: . Occasionally a join using primary key columns in a query can be eliminated because of the data involved. If Oracle determines that all of the 'required' data is available in a single table, then the optimizer will rewrite the query to eliminate the 'unnecessary' join. Oracle has been doing this for years with the limitation that the primary keys involved were single-column keys. In versions 12.2 and later, multi-column primary keys can be used, however there are cases where the join elimination isn't complete depending upon table order in the FROM clause ... Read More