William Sisson

William been working with SQL-DBMSs since the early-nineties. He is British, but has been living and working in Germany for the last sixteen years. He currently works for a company that develops medical software. In the last ten years he has taken a strong interest not just in the practical applications of databases, but also in the logical and mathematical theories that lie behind the relational model. Aside from databases he also programs in C# and JavaScript and takes an interest in languages like Python and Haskell.

William Sisson 04 November 2014

Where in the Application Should Data Validation be Done?

Learn SQL Server

Whereabouts in the application should the business logic of data-validation checks be made? The advantages of a layered approach to validation that includes database constraints, would seem to outweigh the disadvantages. William Sisson explains some interesting issues.… Read more

Learn SQL Server

William Sisson 07 October 2014

Set-based Constraint Violation Reporting in SQL Server

T-SQL Programming

When you're importing data into an RDBMS in bulk and an exception condition is raised because of a constraint violation, you generally need to fix the problem with the data and try again. The error won't tell you which rows are causing the violation. What if you've thousands of rows to search when it happens? There are solutions, writes William Sisson.… Read more

T-SQL Programming