A Tale of Three COUNTs - view details
The COUNT function has three different syntaxes that do two different things. In this video Scott will cover the different syntaxes of the COUNT function and what question each syntax answers.
Highlights from this video:COUNT(*)number of rows that match the WHERE and JOIN condition
COUNT(<expression>)number of rows that had a non-null expression
COUNT(DISTINCT <expression>)
number of rows that had a non-null expression
and much more Source: http://www.learnitfirst.com/Course/160/Video/2363/A-Tale-of-Three-COUNTs.aspx Course: http://www.learnitfirst.com/Course/160/SQL-Queries-2008.aspx Skill Level: 200 (Beginner - Intermediate) Length: 08:45 (22.0MB) Full DetailsTo download this video, log in then then visit the video's detail page and click "download".
Keywords for this video: sql server, queries, aggreages, counts, where, join, expression, null, non-null
This video comes from the SQL Server 2005/2008 Queries online training course, Writing Queries for SQL Server (2005/2008 Edition). And be sure to check out even more SQL Server 2008/2005 Query Writing training videos.
