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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...
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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Why is ArrayDeque better than LinkedList
I am trying to to understand why Java's ArrayDeque is better than Java's LinkedList as they both implement Deque interface.
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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...
Merge and interleave two arrays in Ruby
...ept that the two rows don't conform, leaving #zip as the obvious solution. And I don't believe he meant that he really cared whether a was mutated ... I don't think he was commenting on a mutated vs functional solution at all, he was just trying to describe the pattern.
– Digit...
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. ...
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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Android: Generate random color on click?
I have an ImageView , in which I am programmaticly creating drawables and presenting them to the user. My goal is to click on said ImageView and change the drawable's color.
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Is there a foreach in MATLAB? If so, how does it behave if the underlying data changes?
...ropriate --- you'll be able to test the loop condition at every iteration, and set the value of the loop variable(s) as you wish:
n = 10;
f = n;
while n > 1
n = n-1;
f = f*n;
end
disp(['n! = ' num2str(f)])
Btw, the for-each loop in Java (and possibly other languages) produces unspecifi...
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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