Based on MySQL 5.6.33, including all the bug fixes in it, Percona Server 5.6.33-79.0 is the current GA release in the Percona Server 5.6 series. Percona Server is open-source and free – this is the …[Read more]
Inside the recursive CTE definition (the part in AS (…)), some syntax constraints must be respected […]
a recursive SELECT mustn’t contain GROUP BY, aggregate
(like SUM), ORDER BY, LIMIT, DISTINCT (this rule doesn’t apply to the non-recursive/anchor/seed SELECT)
a recursive SELECT must reference the CTE only once and
only in its
FROM clause, not in any subquery.
MySQL Connector/Node.JS 1.0.4 was recently released as a development milestone release. This is the first version available via npmjs.com. npmjs.com is the central registry for Node.JS packages. This and potential future official MySQL packages can be found using the @mysql organisation. For this to work we had to change the package name to contain that prefix and have chosen the name @mysql/xdevapi as this package provides the implementation of our X DevAPI for Node.JS and we have a free namespace for potential future libraries as part of our Connector/Node.JS product.
Given an existing Node.JS project we can easily install the library:
$ npm install --save @mysql/xdevapi …[Read more]
This Log Buffer Edition goes around and picks up some of the nifty blog posts of the week from Oracle, SQL Server and MySQL.
Smoke and mirrors: monitoring function calls that do not exist anymore
Trace Files Split in Multiple Parts
How can we use Oracle to deduplicate our data
Add systemd Startup Script For CouchDB
Pending statistics and …[Read more]
- What are the common approaches to data replication?
- Why do you want to use data replication in your application?
- What MySQL offers with different replication types.
- What are the limitations of different MySQL replication.
- How to evaluate your architecture needs
- A new architecture mindset …
Generated Columns is a feature released on MySQL 5.7. They can be used during
CREATE TABLE or
ALTER TABLE statements.
It is a way of storing data without actually sending it through
UPDATE clauses in SQL.
The database resolves what the data will be.
There are two types of Generated Columns: Virtual and Stored. They work with:
- mathematical expressions (
- built-in functions (
- literals (“2”, “new”, 0)
Besides that, they can be indexed but they don’t allow …[Read more]
This is the sixth post in a series covering Yelp's real-time streaming data infrastructure. Our series explores in-depth how we stream MySQL updates in real-time with an exactly-once guarantee, how we automatically track & migrate schemas, how we process and transform streams, and finally how we connect all of this into datastores like Redshift and Salesforce. Read the posts in the series: Billions of Messages a Day - Yelp's Real-time Data Pipeline Streaming MySQL tables in real-time to Kafka More Than Just a Schema Store PaaStorm: A Streaming Processor Data Pipeline: Salesforce Connector The Yelp Data Pipeline gives developers a...
I have a habit to keep a log of everything I work on (or even
just read about while working) every day. It's just a plain text
file, with date labels, where most lines are URLs of issues and
bugs I contributed to somehow, and my comments on what I did and
why. But there are also code fragments, texts, copy-pasted
outputs and links to interesting sites, articles and
Some of lines from this log I post on Facebook separately as I add them, these are mostly related to MySQL bugs and other things that annoy me. I know that some of my Facebook friends actually do not like this kind of posts at all... When I used LiveJornal actively, I've posted digests of my log from time to time (you can check what was there if you read Russian). But that digests …
I tweeted this a few days ago and I’ve been thinking more about it.
Databases can just be a log. Everything else is a read optimization.
— Thought retweeter (@PreetamJinka) October 13, 2016
A database is a set of information. You can add, modify, or remove information from that set. All of these types of changes can be expressed as instructions. What happens when you put these instructions together? You get a log.
Starting with an append-only, immutable log as a database makes you think about all kinds of stuff differently. When I started working on lm2, I had a fancy (but still relatively simple) design with block allocation, MVCC, free …[Read more]