Ideas, releases, practical guides, and perspectives from the people building with MySQL.
This Week’s log buffer edition covers some of the useful blog posts from Oracle, SQL Server and MySQL.
Oracle:
ASM disks – lsdg compared with the v$asm_diskgroup view
Can a query on the standby update the primary ?
What should I know about SQL?
Setting Environment Variables in Application Server/Process Scheduler Tuxedo Domains
Oracle …
[Read more]Over the last year, the Ceph world drew me in. Partly because of my taste for distributed systems, but also because I think Ceph represents a great opportunity for MySQL specifically and databases in general. The shift from local storage to distributed storage is similar to the shift from bare disks host configuration to LVM-managed disks configuration.
Most of the work I’ve done with Ceph was in collaboration with folks from Red Hat (mainly Brent Compton and Kyle Bader). This work resulted in a number of talks presented at the Percona Live conference in April and the Red Hat Summit San Francisco at the end of June. I could write a lot about using Ceph with databases, and I hope this post …
[Read more]Percona announces the release of Percona XtraBackup 2.3.5 on July 8, 2016. Downloads are available from our download site or Percona Software Repositories.
Percona XtraBackup enables MySQL backups without blocking user queries, making it ideal for companies with large data sets and mission-critical applications that cannot tolerate long periods of downtime. Offered free as an open source solution, Percona XtraBackup drives down backup costs while providing unique features for MySQL backups.
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[Read more]In this blog post, we’ll look at pipelining versus parallel query execution when using X Plugin for MySQL 5.7.
In my previous blog post, I showed how to use X Plugin for MySQL 5.7 for parallel query execution. The tricks I used to make it work:
I had to do it manually (as well as to sort the result at the end) as X Plugin only supports “pipelining” (which only saves the round trip time) and does not “multiplex” connections …
[Read more]Examples are a great way to learn new things. As many of you may or may not know we’ve added some new things to MySQL Server 5.7.12 and the ecosystem around it, extending it to allow you to use the MySQL as a Document Store. Meeting the challenge meant expanding Developer Interfaces and Database tools.
From the developer side the MySQL Document Store new APIs by …
[Read more]As an update to the previous announcement, please find below list of events where you can find either MySQL Community team or MySQL experts at. Please find more details at each conference below. New events are marked with NEW! Any update to already announced event is marked as UPDATE!:
In this blog post, I discuss some of the insights needed when using Amazon RDS and pt-online-schema-change together.
The pt-online-schema-change tool runs DDL queries (ALTER) online so that the table is not locked for reads and writes. It is a commonly used tool by community users and customers. Using it on Amazon RDS requires knowing about some specific details. First, a high-level explanation of how the tool works.
This is an example from the documentation:
pt-online-schema-change --alter "ADD COLUMN c1 INT" D=sakila,t=actor
The tool runs an ALTER on the table “actor” from the database “sakila.” The alter adds a column named “c1” of type …
[Read more]Recently I experimented with column-level privileges in MySQL. Column-level privileges are fairly straightforward, but given how infrequently they are used I think there are a few areas worth discussing.
Here are a few high-level observations:
INSERT and UPDATE
statements that affect columns they don't have privileges on, as
long as they rely on implicit defaults
DELETE privileges, thus only
SELECT, INSERT, and UPDATE
are supported
GRANT statement or multiple GRANT
statements, the results are cumulative
Read on for more details on each type of …
[Read more]Building a docker image for MySQL is essential if you’d like to customize MySQL to suit your needs. The image can then be used to quickly start running MySQL containers, which can be operated individually. In our previous post, we covered the basics of running MySQL as container. For that purpose, we used the MySQL image from the official Docker repository. In this blog post, we’ll show you how to build your own MySQL image for Docker.
What is a container image?
A container requires an image to run. A container image is like a virtual machine template. It has all the required stuff to run the container. That includes operating system, software packages, drivers, configuration files and helper scripts packed in one bundle.
When running MySQL on a physical host, here is what you would normally do:
It's usually a good practice to have two columns called
date_created and date_updated in every table. One
can always use it in application and it helps in debugging too as
to when a record was created and last updated in various
circumstances and contexts.
This responsibility can be given to MySQL to automatically assign
current time values to these columns.
In MySQL 5.6 onwards, this can be done by setting the data type
of the columns to be either date time or timestamp and creating
date_created column with NOT NULL DEFAULT
CURRENT_TIMESTAMP schema and date_updated column
with NOT NULL DEFAULT …
