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mongo group query how to keep fields
...are accumulated/funneled/reduced) doesn't make so much sense even theoretically. However, sorting before hand is actually inefficient compared to sorting each group within themselves since sorting algorithms are more complex than O(n). I wish there would be better ways in MongoDB.
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How to easily map c++ enums to strings
...xtra syntactic sugar, here's how to write a map_init class. The goal is to allow
std::map<MyEnum, const char*> MyMap;
map_init(MyMap)
(eValue1, "A")
(eValue2, "B")
(eValue3, "C")
;
The function template <typename T> map_init(T&) returns a map_init_helper<T>.
map...
Git keeps asking me for my ssh key passphrase
...-add
This will ask you your passphrase just once, and then you should be allowed to push, provided that you uploaded the public key to Github.
To save key permanently on macOS:
ssh-add -K
This will persist it after you close and re-open it by storing it in user's keychain.
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How can I programmatically check whether a keyboard is present in iOS app?
... responder. I have a view controller with multiple child view controllers, all of which contain UITextFields. Using this method, i cannot tell from my parent view controller whether the keyboard is shown. The only reliable way is to use the notification method explained in the other answers
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Stop “developer tools access needs to take control of another process for debugging to continue” ale
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Per Zev Eisenberg's answer, reinstalling Xcode 4.2.1 worked. However, it might be easier to just patch the /etc/authorization file with the following diff.
<key>system.privilege.taskport.debug</key>
<dict>
<...
SQL Server: Examples of PIVOTing String data
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If you specifically want to use the SQL Server PIVOT function, then this should work, assuming your two original columns are called act and cmd. (Not that pretty to look at though.)
SELECT act AS 'Action', [View] as 'View', [Edit] as 'Edit...
setup.py examples?
...through Python packages on the Python Package Index. Just download the tarball, unpack it, and have a look at the setup.py file. Or even better, only bother looking through packages that list a public source code repository such as one hosted on GitHub or BitBucket. You're bound to run into one on t...
How can I check if a Perl array contains a particular value?
...For the record, this code still does iterate through the array. The map{} call simply makes that iteration very easy to type.
– Kenny Wyland
Mar 3 '12 at 23:09
3
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Postgresql: password authentication failed for user “postgres”
I have installed PostgreSQL 8.4, Postgres client and Pgadmin 3. Authentication failed for user "postgres" for both console client and Pgadmin. I have typed user as "postgres" and password "postgres", because it worked before. But now authentication is failed. I did it before a couple of times withou...
How to remove \xa0 from string in Python?
I am currently using Beautiful Soup to parse an HTML file and calling get_text() , but it seems like I'm being left with a lot of \xa0 Unicode representing spaces. Is there an efficient way to remove all of them in Python 2.7, and change them into spaces? I guess the more generalized question would...