First create this table
CREATE TABLE Teaser (ID int)
INSERT Teaser
VALUES(1)
INSERT Teaser
VALUES(2)
INSERT Teaser
VALUES(1)
INSERT Teaser
VALUES(2)
INSERT Teaser
VALUES(NULL)
Without running this try to figure out what the result will be
SELECT COUNT(*),
COUNT(ID),
COUNT(DISTINCT ID)
FROM Teaser
For some more NULL summer fun you can read
NULL Trouble In SQL Server Land
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About Denis Gobo
I was born in Croatia in 1970, when I was one I moved to Amsterdam (and yes Ajax is THE team in Holland) and finally in 1993 I came to the US. I have lived in New York City for a bunch of years and currently live in Princeton, New Jersey with my wife and 3 kids. I work for Dow Jones as a Database architect in the indexes department, one drawback: since our data goes back all the way to May 1896 I cannot use smalldates ;-(
I have been working with SQL server since version 6.5 and compared to all the other bloggers here I am a n00b.
Some of you might know me from http://sqlservercode.blogspot.com/ or even from some of the newsgroups where I go by the name Denis the SQL Menace
If you are a Tek-Tips user then you might know me by the name SQLDenis, I am one of the guys answering SQL Questions in the SQL Programming forum.