Isolation levels

Isolation levels affect how aggressively SQL Server places and holds locks on tables and schemas. Get too lazy and you’ll end up with phantom data and dirty reads. Be too zealous, and you’ll end up troubleshooting deadlocks. Here’s an overview of the different types of isolation levels available, to help you choose which one is best for you.

Converting JSON data to XML using a T-SQL function

Depending on your line of work, you may some time stumble over JSON data. JSON is a data format specifically designed to work well with Javascripts on web pages, so it’s fairly common in web service applications. If you’ve managed to land JSON data on your server and need to convert it to XML, here’s an idea how to.

Catalog views: Database objects

Catalog views are system views that expose most facets of the server and its databases in a tabular form. In this tutorial, we’ll take a closer look at database objects and how they’re represented in a database’s catalog views.

Table value functions vs Inline functions

Table value functionYou may not know that there are two different ways of writing user-defined functions that return a recordset: Table value functions and Inline functions, and they both come with a number of benefits and limitations with regard to performance and programmability.

Top 10 T-SQL worst practices

BombAs part of an improvement process (any process, not just database development), you can start by asking yourself “How could I make this process as bad as possible”. In fact, when you think of how to royally screw something up, all you have to do is flip the answer around, and there you have a good starting point for improving your process, work, whatever.

Here are a few T-SQL “worst practices” to get you started on improving your database design and development practices. I’ve personally seen all of these in the field, and I think you might recognize some of them, too.