Tag: SQL Server Performance

User-defined scalar functions (scalar UDFs) provide SQL Server developers with an excellent means to organizer and re-use code. Unfortunately, these benefits often come at the price of poor, and in many cases horrendous, performance. Froid is a technology arising from Microsoft Research that addresses these performance problems with novel optimization techniques. In SQL Server 2019, […]

In previous blogs, we took a look at how to install Xperf, and how to use it to look at file I/O. For SQL Server administrators, a potentially important use of Xperf is to examine the consumption of CPU cycles, particularly when tools like the performance counters are showing high CPU use, but the reason […]

SQL Server 2016 enables the creation of natively compiled user-defined functions (UDFs). Since natively compiled UDFs can be used anywhere a function written in TSQL can be used, many people assumed that this would provide an easy route to faster functions. This is not quite the case. Some people even wrote compiled functions that called […]

Is it Better or Worse? What is Cardinality Estimation A fancy-sounding phrase, “cardinality estimation” basically means “guessing how many”. The ability of the query optimizer to select a superior query plan from among many possibilities requires the estimation of how many rows will be extracted from the participating tables and how these rows will be […]