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Add data annotations to a class generated by entity framework
... all situations, In the first case you can describe field validation rules and in the second case try to describe purposes
– dimonser
Mar 31 '15 at 14:14
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A cron job for rails: best practices?
...Listener.process_new_messages
puts "done."
end
To execute from the command line, this is just "rake cron". This command can then be put on the operating system cron/task scheduler as desired.
Update this is quite an old question and answer! Some new info:
the heroku cron service I referenced ...
The apk must be signed with the same certificates as the previous version
I had uploaded my app to Google Play (back when it was called Android Market) some time ago.
11 Answers
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Django - how to create a file and save it to a model's FileField?
Here's my model. What I want to do is generate a new file and overwrite the existing one whenever a model instance is saved:
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What's the fundamental difference between MFC and ATL?
... nothing fancy), what is the fundamental difference I will see between ATL and MFC, to help me figure out which one to use?
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What is compiler, linker, loader?
I wanted to know in depth meaning and working of compiler, linker and loader.
With reference to any language preferably c++.
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Error while installing json gem 'mkmf.rb can't find header files for ruby'
...
For Xcode 11 on macOS 10.14, this can happen even after installing Xcode and installing command-line tools and accepting the license with
sudo xcode-select --install
sudo xcodebuild -license accept
The issue is that Xcode 11 ships the macOS 10.15 SDK which includes headers for ruby2.6, but no...
linq where list contains any in list
...ains method for these kind of queries. I was curious by seeing your answer and checked the internal implementation and found that Intersect uses Set. Can you tell me the performance difference between those two methods?
– rebornx
Feb 17 '17 at 9:02
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LINQ Ring: Any() vs Contains() for Huge Collections
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Contains() is an instance method, and its performance depends largely on the collection itself. For instance, Contains() on a List is O(n), while Contains() on a HashSet is O(1).
Any() is an extension method, and will simply go through the collection, applyi...
Permutations in JavaScript?
...s into an array prior to do any permutation, so you simply remove the join and split operation
var permArr = [],
usedChars = [];
function permute(input) {
var i, ch;
for (i = 0; i < input.length; i++) {
ch = input.splice(i, 1)[0];
usedChars.push(ch);
if (input.leng...