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Madhuka Udantha09/20/14
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Increasing MySQL Connection Count

A short tutorial on increasing the MySQL connection count.

Aleksey Novik09/19/14
6 replies

Solving ORM: Keep the O, Drop the R, No Need for the M

The ORM complexity problem has a simple, production-ready solution hiding in plain sight in the Java world.

Chris Travers09/19/14
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Math and SQL Part 6: The Problem with NULLs

NULL handling is probably the most poorly thought-out feature of SQL and is inconsistent generally with the relational model. Worse, a clear mathematical approach to NULLs is impossible with SQL because too many different meanings are attached to the same value.

Peter Zaitsev09/19/14
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MySQL 101: Monitor Disk I/O with pt-diskstats

In this post, I will share some examples about how to monitor and check to see if the IO subsystem is performing properly or if any disks are a limiting factor – all this by using the pt-diskstats tool.

Lisa Schultz09/19/14
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NoSQL and NewSQL: A Primer

To fulfill the need for additional database processing speed and storage, the goal is to scale-out (add more commodity nodes to the system) rather than having to scale up (add more CPU or memory to each node). And to handle this need, two new kinds of scale-out databases have emerged: NoSQL and NewSQL. Let’s take a look at what sets them apart.

Peter Zaitsev09/18/14
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Generating Test Data from the Mysql> Prompt

There are a lot of tools that generate test data. Many of them have complex XML scripts or GUI interfaces that let you identify characteristics about the data. For testing query performance and many other applications, however, a simple quick and dirty data generator which can be constructed at the MySQL command line is useful.

Lisa Schultz09/18/14
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Report: Vast Majority of Cloud Databases Use SQL

According to a recent survey of 500 developers, 79 percent were using a SQL database—either MySQL or NewSQL—while only 16 percent said they were using NoSQL. At one point in time, industry pundits speculated as to whether NoSQL would threaten SQL’s dominance of the database market. Based on the previous results, this is no longer thought to be the case.

Peter Zaitsev09/17/14
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Trawling the Binlog with FlexCDC and New FlexCDC Plugins for MySQL

Swanhart-Tools includes FlexCDC, a change data capture tool for MySQL. FlexCDC follows a server’s binary log and usually writes “changelogs” that track the changes to tables in the database.

Doug Winfield09/17/14
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Telerik Data Access Enhancer - Persistence and Change Tracking Without Reflection

In this blog post I will talk about the Enhancer – an integral part of Telerik Data Access which often goes unnoticed. The Enhancer is the tool responsible for enabling you to use simple POCO classes in your Telerik Data Access Models and therefore making the development process easier. Let’s see what this tool does for us.

Ayende Rahien09/17/14
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What is New in RavenDB 3.0: JVM Client API

With RavenDB 3.0, we release an official Java Client API for RavenDB. Using it is pretty simple if you are familiar with the RavenDB API or the Hibernate API.

Madolyn Sullivan09/16/14
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Sequence Values in NuoDB

Sequences can be used to auto-generate unique values, such as the primary key column of a table. Sequences also do not respect transactional isolation so they will not cause conflicts if multiple transactions are using the same sequence at the same time. This is why using a Sequence is better than manually maintaining an integer column of a table to assign values.

Peter Zaitsev09/16/14
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A Closer Look at the MySQL ibdata1 Disk Space Issue and Big Tables

A recurring and very common customer issue seen here at the Percona Support team involves how to make the ibdata1 file “shrink” within MySQL. I can only imagine there’s a degree of regret by some of the InnoDB architects on their design decisions regarding disk-space management by the shared tablespace because this has been a big frustration for many MySQL users over the years.

Lisa Schultz09/16/14
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Dealing With Traffic Swings: Why NewSQL Is the Answer

For some e-commerce retailers, predicting spikes and dips in traffic is a relatively easy task. A school supplies retailer, for example, can expect a large influx of traffic in August... But retail traffic isn’t always that predictable. What if your business had to deal with traffic spikes on an unpredictable weekly—or even daily—basis?

Vlad Mihalcea09/15/14
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A Beginners Guide to Database Locking and the Lost Update Phenomena

A database is highly concurrent system. There’s always a chance of update conflicts, like when two concurring transactions try to update the same record.

Peter Zaitsev09/12/14
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Reducer.sh - A Powerful MySQL Test-Case Simplification/Reducer Tool

Let me start by saying a big “thank you” to the staff at Oracle for deciding to open source reducer.sh. It’s a tool I developed whilst I was working for them several years ago. Its sole purpose is to do one thing – but do it good: test-case simplification.

Mike Driscoll09/12/14
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Python 101: An Intro to Pony ORM

The Pony ORM project is another object relational mapper package for Python. They allow you to query a database using generators... In this article, we will spend some time learning the basics of this package.

Lukas Eder09/11/14
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All You Ever Need to Know About Recursive SQL

If you have an intrinsically hierarchical data set, then you will be very unhappy with these simplistic hierarchical SQL features (also with commont table expressions)... But every now and then, a little hierarchy may sneak into your otherwise “standard” relational data model. When it does, be sure to have this useful CONNECT BY clause ready for action.

Vlad Mihalcea09/10/14
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Hibernate Bytecode Enhancement

Now that you know the basics of Hibernate dirty checking, we can dig into enhanced dirty checking mechanisms.

Erik Ejlskov Jensen09/10/14
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Getting and Building the Entity Framework 7 Alpha Bits – Step by Step

This blog post will show you how to get the source code and build it on your own machine, in order to better understand EF 7, and maybe give it a early run. Keep in mind that a number of features are still broken/not implemented...

Michael Collier09/10/14
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Creating a Custom SQL Server VM Image in Azure

Recently I had the opportunity to work on a project were I needed to create a custom SQL Server image for use with Azure VMs. The process was a little more challenging than I initially anticipated... Perhaps this isn’t much of a challenge for an experienced SQL Server DBA or IT Pro. For me, it was a great learning experience.

Peter Zaitsev09/08/14
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mysqld_multi: How to Run Multiple Instances of MySQL

The need to have multiple instances of MySQL (the well-known mysqld process) running in the same server concurrently in a transparent way, instead of having them executed in separate containers, is uncommon. Yet occasionally we receive a request from a customer to assist in the configuration of such an environment.

Lukas Eder09/06/14
4 replies

Awesome SQL Trick: Constraints on Views

CHECK constraints are already pretty great when you want to sanitize your data. But there are some limitations to CHECK constraints, including the fact that they are applied to the table itself, when sometimes, you want to specify constraints that only apply in certain situations. This can be done with the SQL standard WITH CHECK OPTION clause, which is implemented by at least Oracle and SQL Server.

Lukas Eder09/04/14
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Integrating jOOQ with PostgreSQL: Partitioning

jOOQ is a great framework when you want to work with SQL in Java without having too much ORM in your way. At the same time, it can be integrated into many environments as it is offering you support for many database-specific features. One such database-specific feature is partitioning in PostgreSQL.

Alec Noller09/03/14
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Dev of the Week: Hébert Coelho de Oliveira

Every week here and in our newsletter, we feature a new developer/blogger from the DZone community to catch up and find out what he or she is working on now and what's coming next. This week we're talking to Hebert Coelho De Oliveira, Senior Developer at M4U.

Moshe Kaplan09/02/14
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MySQL Installation on Ubuntu

It seems that MySQL was created to be installed on RHEL/CentOS/Fedora... but what if you are actually using Ubuntu? Well, this is the purpose of the following tutorial