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In SQL, what's the difference between count(column) and count(*)?
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count(*) counts NULLs and count(column) does not
[edit] added this code so that people can run it
create table #bla(id int,id2 int)
insert #bla values(null,null)
insert #bla values(1,null)
insert #bla values(null,1)
insert #bla values(1,null)
in...
How does a public key verify a signature?
...m trying to get a better grapple on how public/private keys work. I understand that a sender may add a digital signature to a document using his/her private key to essentially obtain a hash of the document, but what I do not understand is how the public key can be used to verify that signature.
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Difference between Fact table and Dimension table?
...en reading a book for business objects, I came across the term- fact table and dimension table.
9 Answers
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Algorithm for classifying words for hangman difficulty levels as “Easy”,“Medium”, or “Hard”
...angman strategy
There's an idea that's implicit in some the other answers and comments, that the optimal strategy for the solver would be to base their decisions on the frequency of letters in English, or on the frequency of words in some corpus. This is a seductive idea, but it's not quite right. ...
R: rJava package install failing
When installing rJava using the install.packages("rJava") command I get the following error:
16 Answers
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Replace a newline in TSQL
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Actually a new line in a SQL command or script string can be any of CR, LF or CR+LF. To get them all, you need something like this:
SELECT REPLACE(REPLACE(@str, CHAR(13), ''), CHAR(10), '')
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What is the Invariant Culture?
...xample to demonstrate the usage of the Invariant Culture ? I don't understand what the documentation describes.
5 Answers
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How can I change my Cygwin home folder after installation?
I just installed Cygwin, and it looks like the home directory in the bash prompt is on my Z: drive. That's not where I want it.
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Difference between doseq and for in Clojure
What's the difference between doseq and for in Clojure? What are some examples of when you would choose to use one over the other?
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How do I view all commits for a specific day?
I've already looked at the relevant docs from git-scm.com and gitref.org , but I can't seem to figure this out.
5 Answe...