Tag: statistics

Feed: Planet big data. Author: David Smith. As Google learned, predicting the spread of influenza, even with mountains of data, is notoriously difficult. Nonetheless, bioinformatician and R user Shirin Glander has created a two-part tutorial about predicting flu deaths with R (part 2 here). The analysis is based on just 136 cases of influenza A H7N9 in China in 2013 (data provided in the outbreaks package) so the intent was not to create a generally predictive model, but by providing all of the R code and graphics Shirin has created a useful example of real-word predictive modeling with R. The tutorial covers loading and cleaning ... Read More

Feed: SQL Server Release Services. Author: Parikshit Savjani. With cloud first strategy, the SQL Product Team has observed great success and adoption of SQL Server 2016 compared to any previous releases. Today, we are even more excited and pleased to announce the availability of SQL Server 2016 Service Pack 1 (SP1). With SQL Server 2016 SP1, we are making key improvements allowing a consistent programmability surface area for developers and organizations across SQL Server editions. This will enable you to build advanced applications that scale across editions and cloud as you grow. Developers and application partners can now build to ... Read More

Feed: Planet PostgreSQL. It’s a common misconception that high volume read-write workloads in PostgreSQL inevitably causes database inefficiency. We’ve heard of cases where users encounter slowdowns doing only a few hundred writes per second and turn to systems like Dynamo or Cassandra out of frustration. However PostgreSQL can handle these workloads without a problem as long as it is configured correctly. The problems stem from what’s known as “bloat,” a phenomenon of PostgreSQL and other MVCC databases which causes increased space usage and decreased performance. We’ll see how autovacuum, a tool to combat bloat, is typically misunderstood and misconfigured. By ... Read More

Feed: Databasejournal.com - Feature Database Articles. Author: . Oracle 12.1 provides an interesting performance enhancement, the in-memory column store, that can increase performance by reducing physical I/O load by making tables memory-resident (to simplify the description somewhat). Along with the in-memory access to table data Oracle has introduced a new optimization called "Vector Transformation, including Vector Optimization" for in-memory operations. Even when this new optimization isn't in use there are new code paths to take advantage of this technology. As a result execution plans can change; let's look at an example originally provided by Jonathan Lewis that illustrates this. Two ... Read More

Feed: Featured Blog Posts - Data Science Central. Author: Don Philip Faithful. A theme in my blogs is how the "structure" of data - rather than just the "content" - affects what that data can say and is capable of doing. In particular, I suggest that certain structures tend to reinforce certain contents; this means that a structural imposition can have an effect similar to a contextual imposition. Structure is an interesting conversation because, at first glance, arguably data has none. Structure is something that is attributed to physical things. But data normally has no physical existence - at least ... Read More

Feed: SQL Server Customer Advisory Team. Author: Dimitri Furman. Reviewed by: Steven Green, Peng Song, Xiaochen Wu, Kun Cheng, Sanjay Mishra Introduction Database migration from SQL Server to Azure SQL Database is a process that many organizations must implement as they move to Azure public cloud. This article is a guide that describes one specific implementation path for the migration process, that has been commonly used by Microsoft customers. To aid others in the same task, in this article we present lessons learned, recommendations, examples, caveats, potential issues, solutions, and workarounds. A sample PowerShell script that automates some migration steps ... Read More

Feed: Planet MySQL. Author: Ronald Bradford. To focus on just one point for OTN appreciation day on October 11 2016 and to the benefit of all users of MySQL is to consider the extremely convenient and rich value of information available in the MySQL Performance Schema to understand what SQL queries are running in a MySQL instance now. The MySQL Performance Schema in MySQL 5.6 is enabled by default, (performance_schema=on). The following one off SQL statement will enable the instrumentation of SQL statements in the most detailed level of assessment. The following query will show you the longest running queries ... Read More