Louis Davidson

Louis has been in the IT industry for over 20 years as a corporate database developer and data architect. Currently he is the Data Architect for CBN in Virginia Beach. Louis has been a Microsoft MVP since 2004, and is an active volunteer for the PASS locally and globally. He is the author of a series of SQL Server Database Design books, most recently Pro SQL Server Relational Database Design and Implementation.

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15 August 2018
15 August 2018

Teaching a Database Design and Implementation Class in Orlando 9-13

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Thanks to Andy Warren (@sqlandy), on Thursday, September 13, I will be in Orlando, FL teaching an all-day seminar on the process of designing and implementing a relational database, entitled “Constructing a SQL Server Database.” Throughout the following 7 modules, we will make some requirements, model the database, create tables, with foreign keys, check constraints, … Read more
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09 July 2018
09 July 2018

T-SQL Tuesday #104: Code You Would Hate To Live Without (Relative Positioning in Date Table)

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Today’s blog post is in response to Bert Wagner’s invitation here: https://bertwagner.com/2018/07/03/code-youd-hate-to-live-without-t-sql-tuesday-104-invitation/. For me, the answer was pretty simple. There is one piece of code that I have written that I find very useful, and even more… it was my (as far as I know, my own idea!)  In my life, I have obviously learned a … Read more
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30 April 2018
30 April 2018

Operator Precedence versus the Confusing Constraint Translation

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The other day, a person I work with was creating some fairly complex CHECK constraints to protect data in a new table that was being created (a practice I am 100% for: https://www.red-gate.com/simple-talk/blogs/eliminating-annoying-space-characters-via-check-constraints/. The multiple constraints were combined into just one, with several conditions condensed into a single Boolean expression, using several ANDs, ORs, and … Read more
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18 April 2018
18 April 2018

Finding overlapping ranges of data

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This week, I had a problem where I needed to find and eliminate from the results of my query, data with overlapping ranges. I have written about this topic before, in my database design book book, in regards to building a trigger to avoid overlapping ranges. But even though I have written on the topic … Read more
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