Before reading this article, you should have a good understanding of single joins between two tables and be clear on the differences between inner and outer joins. Check out my previous post A Primer on Joins to help you accomplish this. Have you ever looked at a query like the one below and wondered how to read it, … Continue reading Multiple Joins Work just like Single Joins
The golden rule of OLTP database design is that every table should represent one, and only one, entity-type. Without this rule, databases can exhibit three data anomalies (insertion, deletion, and update anomalies) that undermine data integrity. But adherence to the rule comes at a price of greater overhead (though it is a price well worth … Continue reading A Primer on Joins
As we see in the SQL 100 and SQL 250 courses, and as we further explore in this article, joins are used in queries that need to access data stored in more than one table (served up either by the table itself, views, or functions). This article introduces the concept of the “join path” and … Continue reading Exploring Join Paths; The Key to Building Multiple-Table Joins
Though Intellisence is usually a very nice feature to have when working in SQL Server Management Studio (SSMS), it can sometimes get in the way. Here’s how you can disable it if you ever feel the need to: 1. From the Tools menu, select Options. 2. Select the Text Editor option on the … Continue reading How to Disable Intellisence in SSMS
Ever wonder why there are only two options under the INSERT and UPDATE Specification of a foreign key? Why is there no Insert Rule? And to which table in the relationship do these rules apply? Let’s start at the beginning. Relationships in a database are implemented with foreign keys and primary keys. (For a primer … Continue reading Referential Integrity Options (Cascade, Set Null and Set Default)
Contrary to popular belief, prefixing object names isn’t always a good idea and some professionals have dropped the practice entirely. To see why this is, let’s take a look at database object names as an example. Initially, it might seem like a good idea to prefix table names with “tbl,” views with “v,” and so … Continue reading Object Prefixes: Friend or Foe?
Do you need to know how often a report runs, who or what processes run the report, how long it takes to run, statistics on report parameters, which reports are not being used, and so on? SQL Server Reporting Services has built-in audit logging that can give you this type of information pretty easily. Audit … Continue reading How to Audit Report Execution in SSRS
A cover page is simply a page that comes before the report data and that usually contains a report title and other identifying information. It can add clarity to your report and give it a clean, professional look. The cover page usually doesn’t show any data or page numbers, and the first page of data … Continue reading How to Make a Cover Page in SSRS
Business Intelligence (BI) systems were originally targeted primarily at large enterprises with tons of data. As BI technology improved, it started to become more accessible to small- and medium-sized businesses (SMBs), who started using BI systems to answer many of the same business questions as their larger, enterprise cousins. After all, business is business: Whether … Continue reading The Differences Between BI for Enterprises and SMBs
In the 10777 course on data warehouses, we see how to use an SQL Server technology called Change Data Capture. We see how CDC allows data changes made to a line-of-business database to be captured so that we can incrementally update a data warehouse by applying those captured changes to it. We also learn that, before … Continue reading Which Databases and Tables Did You CDC-Enable?