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Gen Furukawa11/20/14
775 views
0 replies

Morpheus Lessons: Best Practices for Upgrading MySQL

Thinking about upgrading your MySQL database? When performing an upgrade, there are some factors you need to consider and some best practices that can be followed to help ensure the process goes as smoothly as possible.

Andreas Kollegger11/19/14
1445 views
0 replies

Neo4j + Docker + CoreOS, a (Gentle) Guided Introduction

I’d like to share with everyone how awesome CoreOS is for leveraging Docker. We use this set up for our search proxy here at Swig (a community for drink enthusiasts for iOS and Android). Neo4j is used as our database and as stated in my previous blog post, it works brilliantly as a startup-friendly (read: flexible) database.

Peter Zaitsev11/18/14
3391 views
0 replies

Data Inconsistencies on MySQL Replicas: Beyond pt-table-checksum

Percona Toolkit’s pt-table-checksum is a great tool to find data inconsistencies between a MySQL master and its replicas. However, you may want to know which exact rows are different to identify the statements that created the inconsistency.

Lukas Eder11/15/14
6435 views
0 replies

Have You Ever Wondered About the Difference Between NOT NULL and DEFAULT?

When writing DDL in SQL, you can specify a couple of constraints on columns, like NOT NULL or DEFAULT constraints. Some people might wonder, if the two constraints are actually redundant, i.e. is it still necessary to specify a NOT NULL constraint, if there is already a DEFAULT clause?

Pat Shaughnessy11/14/14
2395 views
0 replies

Following a Select Statement Through Postgres Internals

This post is an informal journal of my trip through the guts of Postgres. I’ll describe the path I took and what I saw along the way. I’ll use a series of simple, conceptual diagrams to explain how Postgres executed my query.

Peter Zaitsev11/14/14
858 views
0 replies

Percona Live London 2014 Wrap Up

The 2014 edition of Percona Live London brought together attendees from 30 countries to hear insightful talks from leaders in the MySQL community. The conference kicked off on Monday with a full day of tutorials followed by the very popular Community Dinner featuring a double decker bus shuttle from the conference to the event.

Peter Zaitsev11/14/14
570 views
0 replies

Percona Live MySQL Conference Call for Proposals Closes Nov. 16

Submit your speaking proposals now for tutorials or breakout session on the Percona Live conference website. Accepted speakers receive a full conference pass and the sincere gratitude of attendees who will eagerly await your presentations.

Peter Zaitsev11/12/14
2130 views
0 replies

How to Deal with MySQL Deadlocks

A deadlock in MySQL happens when two or more transactions mutually hold and request for locks, creating a cycle of dependencies. In a transaction system, deadlocks are a fact of life and not completely avoidable.

Vlad Mihalcea11/11/14
2751 views
2 replies

An Entity Modelling Strategy for Scaling Optimistic Locking

Optimistic locking discards all incoming changes that are relative to an older entity version. But everything has a cost and optimistic locking makes no difference.

Lukas Eder11/11/14
3561 views
3 replies

Painless Access from Java to PL/SQL Procedures with jOOQ

PL/SQL is one of those things. Most people try to stay clear of it. Few people really love it. I just happen to suffer from stockholm syndrome, since I’m working a lot with banks.

G. Ryan Spain11/10/14
161 views
0 replies

The Best of the Week (Oct. 31): SQL Zone

Make sure you didn't miss anything with this list of the Best of the Week in the SQL Zone (October 31 - November 07). Including Hibernate Collections Optimistic Locking, MySQL full text search Q&A, and an interview with Facebook MySQL DB engineers.

Peter Zaitsev11/08/14
2622 views
0 replies

Backup and Restore of MySQL to OpenStack Swift

MySQL database usage is popular in OpenStack. Core OpenStack services for Compute (Nova), Storage (Cinder), Neutron (Networking), Image (Glance) and Identity (Keystone) all use MySQL database.

Gen Furukawa11/07/14
2546 views
0 replies

How to Handle Huge Database Tables

There's more than one way to 'split' a table.

Joydeep Das11/07/14
932 views
0 replies

Understanding the Execution Plan [When Table JOIN Occurs Part-III]

Continuing our journey here we see some others operators exist in our execution plan. Here is the query and Execution Plan that we are working from couple of weeks.

Abishek Baskaran11/06/14
1340 views
0 replies

Back to Learning Grammar with ANTLR

This post is going to be about language processing. Language processing could be anything like an arithmetic expression evaluator, a SQL parser or even a compiler or interpreter. Many times when we build user facing products, we give users a new language to interact with the product.

Joydeep Das11/05/14
779 views
0 replies

Understanding the Execution Plan [When Table JOIN occurs Part-II]

Continuing my previous article Understanding Execution Plan [ When Table JOIN occurs Part – I ], here we are describing the other process of Execution Plan.

Vlad Mihalcea11/04/14
8374 views
0 replies

Hibernate Collections Optimistic Locking

Hibernate provides an optimistic locking mechanism to prevent lost updates even for long-conversations.

Peter Zaitsev11/04/14
1505 views
0 replies

Facebook MySQL database engineers ready for Percona Live London 2014

I spoke with Facebook database engineers Yoshinori “Yoshi” Matsunobu and Shlomo Priymak about their upcoming sessions along with what’s new at Facebook since our last conversation back in April.

Joydeep Das11/03/14
1505 views
0 replies

Understanding the Execution Plan [When Table JOIN occurs Part-I]

In my previous article we are just using a single table as per our example is concern, Now in this article we are going to see the different table join each other’s and make a single data set by using JOIN.

G. Ryan Spain11/02/14
3338 views
0 replies

The Best of the Week (Oct. 24): SQL Zone

Make sure you didn't miss anything with this list of the Best of the Week in the SQL Zone (October 24 - October 31). Here they are, in order of popularity.

Peter Zaitsev10/31/14
4870 views
0 replies

MySQL 5.6 Full Text Search Throwdown: Webinar Q&A

Yesterday (Oct. 22) I gave a presentation titled “MySQL 5.6 Full Text Search Throwdown.” If you missed it, you can still register to view the recording and my slides. Thanks to everyone who attended, and especially to folks who asked the great questions. I answered as many as we had time for during the session, but here are all the questions with my complete answers

Rob Allen10/30/14
4500 views
0 replies

Setting up PHP & MySQL on OS X Yosemite

Helpful, step-by-step instructions for setting up PHP and MySQL on OS X Yosemite.

Peter Zaitsev10/30/14
940 views
0 replies

Innodb Transaction History Often Hides Dangerous ‘Debt’

In many write-intensive workloads Innodb/XtraDB storage engines you may see hidden and dangerous “debt” being accumulated – unpurged transaction “history” which if not kept in check over time will cause serve performance regression or will take all free space and cause an outage. Let’s talk about where it comes from and what can you do to avoid running into the trouble.

Kevin Rutherford10/28/14
4569 views
1 replies

Where Is the Database?

I have just watched an interesting conversation between Martin Fowler and Badri Janakiraman about #hexagonalrails, and in particular about the role of databases. The central question in the discussion is whether the database should be considered outside or inside the domain.

Vlad Mihalcea10/27/14
2439 views
0 replies

Hibernate Application-Level Repeatable Reads

A Hibernate persistence context can hold one and only one reference of a given entity. The first level cache guarantees session-level repeatable reads.