The Madrid MySQL Users Group has its next meeting on Tuesday, 22nd November 2016. Giuseppe Maxia will be giving a presentation MySQL document store: SQL and NoSQL united and I’ll be providing a brief summary of the new MySQL 8.0 and MariaDB 10.2 beta versions which were announced recently. There will also be an opportunity to … Continue reading MMUG16: MySQL document store: SQL and NoSQL united
The post MMUG16: MySQL document store: SQL and NoSQL united first appeared on Simon J Mudd's Blog.
In this blog, we’ll discuss descending indexes in MySQL 8.0.
Summary
The future MySQL 8.0 will (probably) have a great new feature: support for index sort order on disk (i.e., indexes can be physically sorted in descending order). In the MySQL 8.0 Labs release (new optimizer preview), when you create an index you can specify the order “asc” or “desc”, and it will be supported (for B-Tree indexes). That can be especially helpful for queries like “SELECT … ORDER BY event_date DESC, name ASC LIMIT 10″ (ORDER BY clause with ASC and DESC sort).
MySQL 5.6 and 5.7 Index Order
Actually, the support for this syntax ( …
[Read more]This blog discusses the gradual end of MyISAM in MySQL.
The story that started 20 years ago is coming to its end. I’m talking about the old MyISAM storage engine that was the only storage provided by MySQL in 1995, and was available in MySQL for 20+ years. Actually, part of my job as a MySQL consultant for 10+ years was to discover MyISAM tables and advise customers how to convert those to InnoDB.
(Check your MySQL installation, you may still have MyISAM tables).
MySQL 5.7 still used MyISAM storage for the system tables in the MySQL schema.
In MySQL 8.0 (DMR version as of writing), the MyISAM storage engine is still available. But in a very limited scope:
Today was the first day of sessions at Percona Live Europe 2016, and it was packed with exciting talks and important information on open source databases. Some of the most anticipated talks are those that cover what to expect in MySQL 8.0.
One of those talks was given by Oracle’s Manyi Lu, Director of Software Development. She discussed MySQL 8.0: what’s new in Optimizer.
In her talk, Manyi discussed what we could look forward to in MySQL 8.0’s optimizer. There are substantial improvements in the optimizer in MySQL 5.7 and MySQL 8.0. Most noticeably, users can now combine relational data with NoSQL using the new JSON features. MySQL also now supports functional indexes through generated columns. …
[Read more]In this blog post, we’ll look at MySQL 8.0 general tablespaces.
Introduction
MySQL 8.0 (the DMR version is available now) has two great features (among others):
With those two options, we can use MySQL for creating multi-tenant environments with a “schema per customer” approach.
Schema per Customer with MySQL 8.0
Using schema per customer with older MySQL versions presents issues … namely the number of files. (I’ve described …
[Read more]
MySQL 8.0 now supports the thread sanitizer.
This is good news as the thread
sanitizer provides MySQL developers another tool to help find
bugs in the multi-threaded MySQL server. What happens when
we build MySQL 8.0 with the thread sanitizer enabled and try to
run some basic MySQL tests? Unfortunately, no MySQL tests
run since the MySQL bootstrap fails with lots of data races and
other issues raised by the thread sanitizer. When these
issues are suppressed, some of the basic MySQL and InnoDB tests
pass. Some of these issues are real bugs and need to be
investigated.
Both gcc 6.1 and clang 3.9 support the thread sanitizer.
Just add the 'WITH_TSAN=ON' cmake option when
configuring and building MySQL 8.0, and the MySQL code will be
compiled with the …
MySQL 8.0.0 introduces three new miscellaneous UUID functions of IS_UUID(), UUID_TO_BIN() and BIN_TO_UUID() joining the UUID() (in 5.0) and UUID_SHORT() (in 5.1) functions. See 8.0.0 Release Notes.
Thanks to the great work and hosting by Marcus Popp anybody can test out the SQL syntax of MySQL 8.0.0 using db4free without installing anything. If you want a minimal install Giuseppe Maxia provides docker minimal images of 5.0+ versions …
[Read more]
FRM-less, transactional data dictionary is arguably the most
significant feature change announced MySQL 8.0 development
release. The server still has two separate dictionaries (MySQL,
InnoDB) but the infamous FRM files are finally being replaced
with transactional, InnoDB-based storage.
While this is interesting for various reasons, this particular
post will focus on the impact this change has on data dictionary
performance.
Test configuration Server configuration:
In MySQL 5.7 the new JSON support had been added. The JSON support consists out of three features:
All three features combined allow building very powerful applications without committing to a fixed data structure on every part, but I was missing one thing a lot: Aggregation.
A topic I'm thinking a lot about is finding ways to select nested data. In MySQL we typically have two ways for this. Either one sends multiple queries to retrieve different nesting levels or one builds JOINs which tend to deliver repetitive responses. A tool …
[Read more]Coinciding with the new native data dictionary in MySQL 8.0, we have made a number of useful enhancements to our INFORMATION_SCHEMA subsystem design in MySQL 8.0. In this post I will first go through our legacy implementation as it has stood since MySQL 5.1, and then cover what’s changed.…
