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SQL “select where not in subquery” returns no results
... FROM table1 t1
)
When table1.common_id is not nullable, all these queries are semantically the same.
When it is nullable, NOT IN is different, since IN (and, therefore, NOT IN) return NULL when a value does not match anything in a list containing a NULL.
This may be confusing bu...
Why do enum permissions often have 0, 1, 2, 4 values?
... bit corresponds to some permission (or whatever the enumerated value logically corresponds to). If these were defined as 1, 2, 3, ... you would not be able to use bitwise operators in this fashion and get meaningful results. To delve deeper...
Permissions.Read == 1 == 00000001
Permissions.Writ...
iOS Safari – How to disable overscroll but allow scrollable divs to scroll normally?
...n(e){
e.preventDefault();
});
// Uses body because jQuery on events are called off of the element they are
// added to, so bubbling would not work if we used document instead.
$('body').on('touchstart', selScrollable, function(e) {
if (e.currentTarget.scrollTop === 0) {
e.currentTarget.scrol...
What is ActiveMQ used for - can we apply messaging concept using a Database?
...that up communicating thousands of messages per second, Databases tend to fall over.
Message-oriented middle-ware [MOM] like ActiveMQ on the other hand are built to handle those use cases.
They assume that messages in a healthy system will be deleted very quickly and can do optimizations to avoid t...
Using Git with an existing Xcode project
... Where is the bit about adding a .gitignore file to avoid adding all build directories and other crap as tracked files ???
– Fraggle
Oct 12 '12 at 12:56
7
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What does the “-U” option stand for in pip install -U
...find any docs for pip's command line options/arguments. What does pip install -U mean? Does anyone have a link to a list of pip's options and arguments?
...
How do you rotate a two dimensional array?
...
One of my favorite SO answers of all time. Very instructive!
– g33kz0r
Apr 4 '13 at 2:49
3
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Are 2^n and n*2^n in the same time complexity?
...out when it is okay to ignore terms in a time complexity equation, specifically with non-polynomial examples.
5 Answers
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CSS table-cell equal width
...eems like the answer. I don't know why but if I set the width to 2% it actually scrunges up each column into 2%. But 100% seems to work great. Any idea what's going on there?
– Harry
May 10 '12 at 2:07
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RSpec vs Cucumber (RSpec stories) [closed]
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Totally agree with you Abie! Cucumber integration is vital!
– dpapadopoulos
Jan 21 '19 at 9:37
add a co...