This will be a multi-part series covering various areas of failover for MySQL. This first installment will primarily look at some design considerations, which you can then apply to your own environment in your own way. The concepts presented here are merely suggestions and not out-right “how-to”. Every company has specific technologies or skill-sets in… Read More »
I worked on an issue last recently where a query was too slow when executed in MySQL Cluster. The issue was that Cluster has some restrictions when it comes to push down conditions.
As an example of this, consider the following query using the employees sample database. The query takes a look at the average salary based on how many years the employee has been with the company. As the latest hire date in the database is in January 2000, the query uses 1 February 2000 as the reference date.
Initially the query performs like (performance is with two data
nodes and all nodes in the same virtual machine on a laptop, so
the timings are not necessarily representative of a production
system, though the improvements should be repeatable):
mysql> SELECT FLOOR(DATEDIFF('2000-02-01', hire_date)/365) AS LengthOfService, COUNT(DISTINCT employees.emp_no) AS NoEmployees, AVG(salary) AS AvgSalary FROM salaries …[Read more]
The MySQL Utilities Team is pleased to announce a new GA release
of MySQL Utilities. This release includes a number of
improvements for usability, stability, and a few enhancements for
better compatibility with MySQL 5.7. A complete list of all
improvements can be found in our release notes.
Many Improvements!
This release represents a stable release of the product and is a
significant improvement from the 1.5 release. Along with defect
patches, we also include the following enhancements.
- Support for MySQL 5.7
- New! Binlog Utilities:
- mysqlbinlogpurge - purge old binary logs
- mysqlbinlogrotate - rotate the binary log
- mysqlbinlogmove - relocate binary log files
- New! Replication Utilities:
- …
This post discusses how XtraDB Cluster and Ceph are a good match, and how their combination allows for faster SST and a smaller disk footprint.
My last post was an introduction to Red Hat’s Ceph. As interesting and useful as it was, it wasn’t a practical example. Like most of the readers, I learn about and see the possibilities of technologies by burning my fingers on them. This post dives into a real and novel Ceph use case: handling of the Percona XtraDB Cluster SST operation using Ceph snapshots.
If you are familiar with Percona XtraDB Cluster, you know that a full state snapshot transfer (SST) is required to provision a new cluster node. Similarly, SST can also be triggered when a cluster node happens to have a corrupted …
[Read more]Founded in St. Paul, Minnesota, API Outsourcing is atechnology company and provider of Centreviews Business Intelligence Suite, asimple, scalable, and secure solution for back office departments andprofessionals to automate their accounts payable, accounts receivable anddocument management processes. Manyenterprises adopt finance and accounting technologies not only to driveefficiency, improve business performance, and reduce operating costs, but evenmore importantly, to allow their resources to focus on core competencies inproducts and service offerings.
Centreviews Business Intelligence Suite is available tocustomers or business partners on a SaaS only model or as a BPaaS model whereAPI provides outsourced labor to process accounts payable, accounts receivable,document management on its Centreviews Business Intelligence Suite. Both theSaaS and BPaaS offering enables customers to …
[Read more]“Complicated queries, like looking for second degree friends, is really hard to traditional databases.” –Dong Bin
I have interviewed Dong Bin, Engineer Manager at LinkedIn China. The LinkedIn China development team launched a new social platform — known as Chitu — to attract a meaningful segment of the Chinese professional networking market.
RVZ
Q1. What is your role at LinkedIn China?
Dong Bin: I am an Engineer Manager in charge of the backend services for Chitu. The backend includes all Chitu`s consumer based features, like feeds, chat, event, etc.
Q2. You recently launched a new social platform, called Chitu. Which segment of the …
[Read more]The MySQL Document Store functionality allows developers to use a relation database with or without SQL (structured Query Language), also known as NoSQL. The example in this blog is hopefully a simple look at this new feature of MySQL. The example data used is from JSONStudio.com and is a JSON formatted data set for US zip (postal) codes (656K compressed). So download your copy of this data set and lets get to work.
Create a collectionCollections are tables and below we create a collection name 'zip' in the test database in the Python dialect.
[Read more]
mysqlsh -u root -p --py test
Creating an X Session to root@localhost:33060/test
Enter password:
Default schema `test` accessible through db.
Welcome to MySQL Shell 1.0.4 Development Preview
Copyright (c) 2016, Oracle and/or its affiliates. …
Welcome to this week’s Planets9s, covering all the latest resources and technologies we create around automation and management of open source database infrastructures.
Sign up for our webinar on MySQL Query Tuning - Process &
Tools
Join us for the first part of our upcoming webinar trilogy on MySQL Query Tuning led by Krzysztof Książek, Senior Support Engineer at Severalnines. This session focuses on the query tuning process and related tools. Building, collecting, analysing, tuning and testing will be discussed in detail as well as the main tools involved, tcpdump and pt-query-digest. |
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The “DBMS” part of MySQL is fine – storage engines (especially with new kids on the block), replication, etc, but it really sucks at executing SQL.
I won’t even get into complex SQL that has complex data dependencies, will start with very basic tasks.
SELECT * FROM table WHERE indexed = "A" LIMIT 1
If multiple indexes can satisfy the query, MySQL will hit each of them at least twice – looking up first “A” and last “A” records. It will do that while planning the SQL execution. Once it comes up with a plan, it will go and hit the index it picked again, this time once. So, if you have two candidate indexes, you will have 5 index accesses at 4 positions.
How would a direct cursor access work? Single index hit. Want to simulate that in SQL? You can add a ‘FORCE INDEX’ hint, then only one …
[Read more]In this post, I’ll review Docker multi-host network performance.
In a past post, I tested Docker network. The MySQL Server team provided their own results, which are in line with my observations.
For this set of tests, I wanted to focus more on Docker networking using multiple hosts. Mostly because when we set up a high availability (HA) environment (using Percona XtraDB Cluster, for example) the expectation is that instances are running on different hosts.
Another reason for this test is that Docker recently announced the 1.12 release, which supports Swarm Mode. Swarm Mode is quite interesting by …
[Read more]