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Peter Zaitsev09/17/14
1158 views
0 replies

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
1661 views
0 replies

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
140 views
0 replies

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
1414 views
0 replies

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
387 views
0 replies

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
269 views
0 replies

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
1580 views
0 replies

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
2619 views
0 replies

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
2312 views
0 replies

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
1886 views
0 replies

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
4055 views
0 replies

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
1279 views
0 replies

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
830 views
0 replies

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
3069 views
0 replies

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
1673 views
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
2008 views
0 replies

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
7110 views
0 replies

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
3051 views
0 replies

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

Lukas Eder09/01/14
1985 views
0 replies

PL/SQL Backtraces for Debugging

For many PL/SQL developers, this might be common sense, but for one of our customers, this was an unknown PL/SQL feature: Backtraces.

Alec Noller08/31/14
4353 views
0 replies

The Best of the Week (July 28): SQL Zone

Make sure you didn't miss anything with this list of the Best of the Week in the SQL Zone. This week's best include JPA Hibernate alternatives, the wonderful SQL feature of quantified comparison predicates, sequence values in NuoDB, and more.

Vlad Mihalcea08/29/14
3506 views
0 replies

The Anatomy of Hibernate Dirty Checking

The persistence context enqueues entity state transitions that get translated to database statements upon flushing. For managed entities, Hibernate can auto-detect incoming changes and schedule SQL UPDATES on our behalf. This mechanism is called automatic dirty checking.

Madolyn Sullivan08/28/14
2358 views
0 replies

Sequence Values in NuoDB

Ever wonder why your Sequence numbers in NuoDB are not necessarily assigned in sequential order?

Jonas Gauffin08/26/14
1275 views
0 replies

How to Create a SqlException

Have you tried to create a SqlException only to discover that the constructor is private? Here is how you can create the exception despite that.

Hebert Coelho D...08/25/14
33983 views
5 replies

JPA Hibernate Alternatives: When JPA & Hibernate Aren't Right for Your Project

Today we will talk about situations in which the use of the JPA/Hibernate is not recommended. What problems do JPA/Hibernate present, what are some solutions, and what alternatives do we have outside of the JPA world?

Chris Travers08/25/14
3207 views
0 replies

Math and SQL Part 5: Projection and Selection

The SELECT statement is the workhorse of SQL. Updates and inserts are necessary, but selects are where the power is. One of the issues many people have in understanding these and using them is a clear understanding of the math involved, because there are a large number of implicit possibilities in the syntax.