Cursor-Killing: Accessing Data in the Next Row

Cursors are considered by many to be the bane of good T-SQL. What are the best ways to avoid iterative T-SQL and to write queries that look and perform beautifully? This first part in an ongoing series of cursor-killing handles inter-row analysis.

Reaping the benefits of the Window functions in T-SQL

Exploring the potential benefits of the T-SQL Window functions (OVER, LAG, and LEAD) in this piece. You can learn how to achieve up to 50% performance boost by replacing a single function call.

The Performance of the T-SQL Window Functions

Window Functions in SQL greatly simplify a whole range of financial and statistical aggregations on sets of data. Because there is less SQL on the page, it is easy to assume that the performance is better too: but is it? Dwain gets out the test harness to investigate.

All the rows before this one

Windowing Ranges

High-Performance Transact-SQL with Window Functions

Window functions are more intuitive and simpler in many cases than alternative SQL methods.

Window Functions in SQL

SQL's windowing functions are surprisingly versatile, and allow us to cut out all those self-joins and explicit cursors. Joe Celko explains how they are used, and shows a few tricks such as calculating deltas in a time series, and filling in gaps.

Calculating Values within a Rolling Window in Transact SQL

Before the SQL Window functions were implemented, it was tricky to calculate rolling totals or moving averages efficiently in SQL Server. There are now a number of techniques, but which has the best performance? Dwain Camps gets out the metaphorical stopwatch.

SQL Server 2012 Window Function Basics

For some time, Microsoft had a few window functions, but not the full set specified in the SQL 2003 standard. Now, in SQL Server 2012 we have the whole range, and extremely useful they are too. There's no longer an excuse to avoid them, particularly now you have Rob Sheldon's gentle introduction.

SQL Server : Usage of OVER Clause

Over  clause can be used in association with aggregate function and ranking function. The over clause determine the partitioning and...