T-SQL

Indexing for Windowing Functions

Indexing, SQL Server, T-SQL
6 Comments
Hooray Windowing Functions They do stuff that used to be hard to do, or took weird self-joins or correlated sub-queries with triangular joins to accomplish. That’s when there’s a standalone inequality predicate, usually for getting a running total. With Windowing Functions, a lot of the code complexity and inefficiency is taken out of the picture,…
Read More

Refactoring T-SQL with Windowing Functions

SQL Server, T-SQL, Videos
6 Comments
You’ve been querying comparative numbers like Year To Date and Same Period Last Year by using tedious CTEs and subqueries. Beginning with SQL Server 2012, getting these numbers is easier than ever! Join Doug for a 30-minute T-SQL tune-up using window functions that will cut down dramatically on the amount of code you need to…
Read More

How to Cache Stored Procedure Results

SQL Server, T-SQL
23 Comments
Say you run an online store, and on each item’s page, you need to show related items that people purchased. Let’s take an Amazon page for my favorite rechargeable AA batteries: Frequently Bought Together In a perfect world, we would cache this data in the web/app tier – but back here in the real world,…
Read More
Query Execution Plan

Sargability: Why %string% Is Slow

T-SQL
44 Comments
People love to search. Google has us addicted to fast, easy search functions.  Users expect every application to have a built-in blazing-fast search functionality.  To pull that off, developers build search queries that let users enter a string, and we ask SQL Server to find matches.  For example, say our users need to find some…
Read More