SQL Server concepts – Page 6

The SQL Server security model, part 1: principals

There are a number of layers in the SQL Server security model, giving you a nearly infinite number of ways to set up access control on your server and databases. Security is a huge topic, and there are literally entire books on it, so this series of articles is designed to give you just a quick overview of the SQL Server security model to get you started.

In this first installment, I’ll go through the different types of security principals that are available, as well as how they connect to each other.

Schemabinding and table spools

There are obvious advantages as well as challenges to schemabinding things, and whether you do or don’t is often a matter of preference. However, in some cases, you need schemabinding; when you’re designing indexed views, and to optimize user-defined functions. Here’s why:

Blocking/non-blocking aggregate operators

Some database operations can be performed in distinctly different manners, with different impacts on query performance. One important example of such an operation is calculating an aggregate. In this article, we’ll take a look at how aggregates can be “blocking” or “non-blocking”, how it affects memory allocation, and ultimately, what impact this has on your query.

Datawarehouse modelling: Inmon vs Kimball

If you’re into business intelligence, data warehousing and analytics, you will have heard an endless number of references to Bill Inmon and Ralph Kimball. These two figureheads in datawarehousing architecture have produced an immense number of books, articles, training seminars, etc. While many of their strategies and modelling approaches are similar, they have near-opposite views on other aspects.

HASH JOIN deep-dive

Among the three different types of join operators used by SQL Server, the HASH JOIN does some of the hardest work. It scales pretty well and is very suitable for parallel processing. As such, it can be very powerful in many applications, but hash joins can potentially consume quite a bit of memory, so seeing on in your query plan could be an indicator of a performance tuning issue in your query or data.

The article deals with some common misconceptions about table variables and it’s considerably more in-depth than my post on different types of temp tables.

Category: SQL Server concepts

Schemabinding and table spools

Blocking/non-blocking aggregate operators

Datawarehouse modelling: Inmon vs Kimball

HASH JOIN deep-dive

An introduction to filtered indexes

Minimally logged operations

Introduction to partitioning

Error handling using TRY-CATCH

Temp table myths