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One of the cool things about the separation of the Dot Net CLR and the Dot Net Compiler is that newer syntax implementations may be made in the compiler that are backward compatible with the Dot Net libraries that the CLR supports. If that confuses you, just hang on and I’ll lay out some examples that should make it more […]
We’ve been looking at some of the set based operations that are part of the SQL Language, and different ways to achieve the same results. Today we add to the discussion the UNION operation. There are two varieties of the UNION operator, UNION and UNION ALL. The UNION operator takes two sets of data, combines the results, and then returns […]
We recently talked about the logical Semi Join operation and the Anti Semi Join operation, and demonstrated method to generate those logical joins using traditional SQL operations found in just about any SQL engine. They are produced by using the IN or EXISTS operation for a Semi Join, or the NOT IN or NOT EXISTS operations for an Anti Semi […]
I have written in the past about using previous versions of a project as the requirements for a new and better product as being an exercise in futility. Without requirements, you don’t know where your are or when you are done. Today I want to talk about another process that is somewhat similar. That is where you have inadequate requirements […]
One of the things I like to do when a new version of a database engine is released is to compare the performance of different query techniques. Doing this comparison results in information that helps in understanding the optimizations that have been introduced with each release. I find it helpful to dispel assumptions of how certain syntax typically performs under […]
One of my favorite things to ask during an interview for a developer who is going to be working with databases is to enumerate the different kinds of joins that are standard in most SQL engines. Not only naming what they are, but how the work, or better yet, how they may be utilized is a great follow on series […]
From a conversation we were having in the comments from last week I was comparing the query plan produced from using different ways to retrieve the same results from the database. Just for fun, I used a new SQL Server 2014 instance for my test, comparing two system tables, sys.sysobjects and sys.indexes. I wanted to find a list of all […]
SQL Server supports the concept of a SEMI JOIN in the many different forms: LEFT SEMI JOIN LEFT ANTI SEMI JOIN RIGHT SEMI JOIN RIGHT ANTI SEMI JOIN The key thing to know about a SEMI JOIN is that it only returns the results from one table. If you use a LEFT SEMI JOIN or LEFT ANTI SEMI JOIN, it […]
I’m wondering about the direction Microsoft is taking with the licensing of the SQL Server engine. Because of the per core licensing model you can carve out how you wish to use the licenses rather nicely. Say you purchase licenses for four cores, because the physical server has four cores, you can use them with different configurations. Say you have […]
In my opinion, privacy is going to be the pivot point to the ultimate success of AI and the Internet of Things. For example, the ability of IOT to capture health factors for an individual allows for applications to make suggestions, or even control different features that improve the quality of life for an individual. Those kinds of applications require […]