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Fast way to discover the row count of a table in PostgreSQL
...of rows due to the nature of MVCC. There is a way to speed this up dramatically if the count does not have to be exact like it seems to be in your case.
Instead of getting the exact count (slow with big tables):
SELECT count(*) AS exact_count FROM myschema.mytable;
You get a close estimate like ...
CORS Access-Control-Allow-Headers wildcard being ignored?
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Support for wildcards in the Access-Control-Allow-Headers header was added to the living standard only in May 2016, so it may not be supported by all browsers. On browser which don't implement this yet, it must be an exact match: https://www.w3.org/TR/2014/REC-cors-201...
What is the difference between char, nchar, varchar, and nvarchar in SQL Server?
...torage space for number of characters you specify even if you don't use up all that space.
varchar and nvarchar are variable-length which will only use up spaces for the characters you store. It will not reserve storage like char or nchar.
nchar and nvarchar will take up twice as much storage spac...
How can I setup & run PhantomJS on Ubuntu?
... to add one additional symlink to /usr/bin/, and I did direct symlinks for all 3 - see below.
I'm installing on Ubuntu server Natty Narwhal.
This is exactly what I did.
cd /usr/local/share
sudo wget https://bitbucket.org/ariya/phantomjs/downloads/phantomjs-1.9.7-linux-x86_64.tar.bz2
sudo tar xjf ...
What is the difference between pip and conda?
...now pip is a package manager for python packages. However, I saw the installation on IPython's website use conda to install IPython.
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C++ display stack trace on exception
...re details.
On MSVC then you can use the StackWalker library that handles all of the underlying API calls needed for Windows.
You'll have to figure out the best way to integrate this functionality into your app, but the amount of code you need to write should be minimal.
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Check if a user has scrolled to the bottom
...ight of the visible window and checks if that equals the height of the overall content (document). If you wanted to instead check if the user is near the bottom, it'd look something like this:
$(window).scroll(function() {
if($(window).scrollTop() + $(window).height() > $(document).height() ...
A transport-level error has occurred when receiving results from the server [closed]
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Can you provide some details on what that actually does? Are there any reasons against setting such a value globally?
– Drew Noakes
Dec 5 '10 at 19:02
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Can anyone explain python's relative imports?
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Thanks, but this honestly seems really silly. For such a beautiful language, I can't believe the designers would create such a restriction. Isn't there any other way?
– carl
Dec 16 '09 at 23:48
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Set active tab style with AngularJS
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i actually haven't been able to get this working. would you be able to provide a plnkr?
– PPPaul
Mar 7 '13 at 22:44
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