Nov 03

My links of the week – November 3, 2013



The most visited post here is the one on my experience with performance on Azure, using WA SQL and VMs. There seems to be a lot of interest in the subject, so in the links for this week, there are quite a few links to articles by the Microsoft SQL Server Support Team on Windows Azure SQL Server. Articles on jQuery, CSS and scalabilty are also featured. 

  • Microsoft SQL Server Support Team’s Windows Azure SQL Database (WASD) Primer is the first of a series of articles on what is known as Windows Azure SQL – the Azure hosted Platform as a Service version of SQL Server. This first article presents some of the terminology used on the article series on WASD and includes some reference links that help understanding the differences between WASD and a “normal” SQL Server installation.
  • Is my query running fine in the cloud? is another of the articles in the series. Addresses several resources that can be used to determine causes of performance issues with WASD – available DMVs, performance, connectivity and resource usage related, execution plans. Again, it includes references to other relevant articles. It should also include a link to scripts to collect DMV info, updated for WASD, but I couldn’t find the article.It is still very informative, even without the link.
  • Do I need to upgrade my DBA skills for the cloud?, yet another article in the series, addresses some of maintenance / administration tasks needed, once the database is online. The series includes two more articles, on firewall configuration to secure access to the database and on getting a database to Azure, that are accessible from any of the articles in the series.
  • Slightly changing subjects, Brent Ozar’s What Developers Need to Know About SQL Server presents advice gathered through a Twitter session on what DBA’s think developers need to know about SQL Server. It has very interesting advice for developers using SQL Server for persistence.
  • Joe Celko’s Window Functions in SQL addresses the whole range of windowing functions in SQL, from aggregate to ranking and analytic functions, with some examples included. A very interesting read.
  • Jeremy Girard’s Selling Responsive Web Design To Clients, starting with a situation where a customer wasn’t interested on having a website redesign, presents a few benefits of responsive design, that usually are not primary motivators for responsive design adoption and concludes that these benefits can be, by themselves, a good way to sell responsive design.

That’s all for this week, thanks for reading.

The image used on this post was originally posted on Wayne Walter Berry’s Inside Windows Azure SQL Database

Oct 06

My links of the week – October 6, 2013

Our weekly reading found a lot of interesting posts, this past week, so making a choice on the posts to include was quite hard. Again, some posts were not originally posted this week, but they are interesting enough. So let’s begin.

  • Richard Morris’ Developing for Delivery, a Practical Example addresses the difficulties of keeping a database current, when the database exists in a multiple number of sites, in a wide range of versions and how such difficulties were addressed by Calvi, a provider of telecom invoicing software. From personal experience, this is not an easy thing to achieve, even at a smaller scale, and the article provides interesting advice on how changes in processes and the use of adequate software tools can help reduce the difficulties involved.
  • Alex Bolenok’s NULL in SQL: explaining its behavior is a very good article on the idiosyncrasies of NULL behavior in SQL. The use of NULLs is not at all clear, especially for developers less familiar with the workings of databases, so the article is almost of mandatory reading. Most interesting.
  • Microsoft’s SQL Server Development Customer Advisory Team’s SQLCAT’s Guide to: Relational Engine is a free ebook that includes relevant posts from SQLCAT’s blog, from 2005 to 2012. Recommended.
  • Rob Farley’s Spooling in SQL execution plans is a few month’s old post, but one that clearly shows why spools are used in SQL Server execution plans and why they are not that bad.
  • Alex Popescu’s The premature return to SQL is a response to one article include in last week’s links, by Jack Clark, in which the author explains why the premature return to “SQL” is wrong – this “premature” return is motivated by an attempt to capture financial gains, does not consider the fact that many NoSQL products, in spite of having not yet reached technical maturity, have already provided valuable, alternative new doors to data and results, basically, from pressure from database vendors. 
  • Uncle Bob Martin’s Dance you Imp’s is a humorous but no less interesting article on Object Relation Mappers and the impedance mismatch between OO and the RDBMS storage used to persist them. In a very funny way, the author concludes that there is actually no object to relational mapping. A very interesting read.
  • Jimmy Bogard’s Scaling lessons learned–from 0 to 15 million users describes the lessons learned while building a system that has grown to handle up to 15 million users over the last 3 years. It is an excellent read and the lessons can be of use to any who develops systems that need to be able to scale (and even for those that don’t have such a need).
  • Sean Hull’s 20 Obstacles to Scalability addresses some key points to consider, when designing a web application that will need to scale. Although based on a MySQL based web app, the advice is general enough and applicable to any RDBMS based web application.
  • James Turner’s What Developers Can Learn from addresses some of the issues exhibited by the website, to draw more general lessons regarding load testing, good looks vs. functionality, and validation, that can be of value to any website. A very good read.
  • Chris Andrè Dale’s Why it’s easy being a hacker – A SQL injection case study, although from last January, addresses the issue of SQL injection vulnerabilities and the fact that many easily available teaching materials used by developers may actually contribute to the persistence of such vulnerabilities. It is a very good read and it draws the attention to one issue that can, indeed, have negative consequences – the  influence of teaching materials on developers and their work. This is an issue that will deserve a future post here.

 That’s it for this week. Thanks for reading.