SQL Clone
SQLServerCentral is supported by Redgate
 
Log in  ::  Register  ::  Not logged in
 
 
 


What's the count?


What's the count?

Author
Message
Slick84
Slick84
Hall of Fame
Hall of Fame (3.5K reputation)Hall of Fame (3.5K reputation)Hall of Fame (3.5K reputation)Hall of Fame (3.5K reputation)Hall of Fame (3.5K reputation)Hall of Fame (3.5K reputation)Hall of Fame (3.5K reputation)Hall of Fame (3.5K reputation)

Group: General Forum Members
Points: 3490 Visits: 1163
Comments posted to this topic are about the item What's the count?

--
Hehe
SQLRNNR
SQLRNNR
SSC Guru
SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)

Group: General Forum Members
Points: 143697 Visits: 18650
Thanks for the question. Nice job.

Jason...AKA CirqueDeSQLeil
_______________________________________________
I have given a name to my pain...MCM SQL Server, MVP
SQL RNNR
Posting Performance Based Questions - Gail Shaw
Learn Extended Events

Arjun SreeVastsva
Arjun SreeVastsva
SSCarpal Tunnel
SSCarpal Tunnel (4.6K reputation)SSCarpal Tunnel (4.6K reputation)SSCarpal Tunnel (4.6K reputation)SSCarpal Tunnel (4.6K reputation)SSCarpal Tunnel (4.6K reputation)SSCarpal Tunnel (4.6K reputation)SSCarpal Tunnel (4.6K reputation)SSCarpal Tunnel (4.6K reputation)

Group: General Forum Members
Points: 4612 Visits: 1711
Nice Question ....Today i learned this from Central...Good Question
jshailendra
jshailendra
Ten Centuries
Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)

Group: General Forum Members
Points: 1182 Visits: 455
Good question..never thought of using count(*) for 2 tables in one T-SQL...thanks for question
aamirjani4u
aamirjani4u
Forum Newbie
Forum Newbie (7 reputation)Forum Newbie (7 reputation)Forum Newbie (7 reputation)Forum Newbie (7 reputation)Forum Newbie (7 reputation)Forum Newbie (7 reputation)Forum Newbie (7 reputation)Forum Newbie (7 reputation)

Group: General Forum Members
Points: 7 Visits: 10
count is basically. Counting the each record of that table.
For Example. Table A has 3 rows then count = 3. if table B has 4 Rows then count=4.
If combine both tables then 3 * 4 = 12 rows and count = 12
Carlo Romagnano
Carlo Romagnano
SSChampion
SSChampion (12K reputation)SSChampion (12K reputation)SSChampion (12K reputation)SSChampion (12K reputation)SSChampion (12K reputation)SSChampion (12K reputation)SSChampion (12K reputation)SSChampion (12K reputation)

Group: General Forum Members
Points: 12311 Visits: 3514
if one table has one o more rows and the other is void, the result is 0.
NumberOfRows * 0 = 0
Sree Divya
Sree Divya
Hall of Fame
Hall of Fame (3.4K reputation)Hall of Fame (3.4K reputation)Hall of Fame (3.4K reputation)Hall of Fame (3.4K reputation)Hall of Fame (3.4K reputation)Hall of Fame (3.4K reputation)Hall of Fame (3.4K reputation)Hall of Fame (3.4K reputation)

Group: General Forum Members
Points: 3393 Visits: 441
In Point of Interview Very Intelligence Question ......Nice...hmmmmm My Answer is Correct............!
kaspencer
kaspencer
Hall of Fame
Hall of Fame (3.1K reputation)Hall of Fame (3.1K reputation)Hall of Fame (3.1K reputation)Hall of Fame (3.1K reputation)Hall of Fame (3.1K reputation)Hall of Fame (3.1K reputation)Hall of Fame (3.1K reputation)Hall of Fame (3.1K reputation)

Group: General Forum Members
Points: 3138 Visits: 902
That's is a good question, illustrating the need for careful joins!

For those that don't know, this kind of result is called a "cartesian product", and if you allow it to happen in a real-world application with even a few hundred rows in either table, you are in for something of an explosion of complaints from your users, to say the least.

Ken.

You never know: reading my book: "All about your computer" might just tell you something you never knew!
lulu.com/kaspencer
nigel.
nigel.
SSCertifiable
SSCertifiable (6.5K reputation)SSCertifiable (6.5K reputation)SSCertifiable (6.5K reputation)SSCertifiable (6.5K reputation)SSCertifiable (6.5K reputation)SSCertifiable (6.5K reputation)SSCertifiable (6.5K reputation)SSCertifiable (6.5K reputation)

Group: General Forum Members
Points: 6450 Visits: 2985
Very good question.

However I think that the explanation is a bit lacking, and could explain in more detail what is happening here and what a 'cross join'/'cartesian product' is.

Here are some links that may help:

Cross Join
Cartesian Product

--
Nigel
Useful Links:
How to post data/code on a forum to get the best help
The "Numbers" or "Tally" Table - Jeff Moden

Daniel Bowlin
Daniel Bowlin
SSCoach
SSCoach (17K reputation)SSCoach (17K reputation)SSCoach (17K reputation)SSCoach (17K reputation)SSCoach (17K reputation)SSCoach (17K reputation)SSCoach (17K reputation)SSCoach (17K reputation)

Group: General Forum Members
Points: 17358 Visits: 2629
This one definitely made me think a minute or two.
Go


Permissions

You can't post new topics.
You can't post topic replies.
You can't post new polls.
You can't post replies to polls.
You can't edit your own topics.
You can't delete your own topics.
You can't edit other topics.
You can't delete other topics.
You can't edit your own posts.
You can't edit other posts.
You can't delete your own posts.
You can't delete other posts.
You can't post events.
You can't edit your own events.
You can't edit other events.
You can't delete your own events.
You can't delete other events.
You can't send private messages.
You can't send emails.
You can read topics.
You can't vote in polls.
You can't upload attachments.
You can download attachments.
You can't post HTML code.
You can't edit HTML code.
You can't post IFCode.
You can't post JavaScript.
You can post emoticons.
You can't post or upload images.

Select a forum








































































































































































SQLServerCentral


Search