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add column to mysql table if it does not exist
... MySQL prior to 5.0. Nor are stored procedures supported prior to 5.0, so if you need to support MySQL 4.1, this solution isn't good.
One solution used by frameworks that use database migrations is to record in your database a revision number for the schema. Just a table with a single column and ...
mongo group query how to keep fields
...
If you want to keep the information about the first matching entries for each group, you can try aggregating like:
db.test.aggregate({
$group: {
_id : '$name',
name : { $first: '$name' },
age : { $first: '$age' },...
How to export collection to CSV in MongoDB?
...hemaless; CSV, on the other hand, has a fixed layout for columns. Without knowing what fields are used in different documents it's impossible to output the CSV dump.
If you have a fixed schema perhaps you could retrieve one document, harvest the field names from it with a script and pass it to mong...
Adding gif image in an ImageView in android
...animation is there. It's appearing just as a still image. I would like to know how can i show it as a gif image.
18 Answers...
How do I check if a number evaluates to infinity?
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if (result == Number.POSITIVE_INFINITY || result == Number.NEGATIVE_INFINITY)
{
// ...
}
You could possibly use the isFinite function instead, depending on how you want to treat NaN. isFinite returns false if your numbe...
android: move a view on touch move (ACTION_MOVE)
I'd like to do a simple control: a container with a view inside. If I touch the container and I move the finger, I want to move the view to follow my finger.
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Getting a list of all subdirectories in the current directory
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For anyone concerned about performance differences between os.walk and os.listdir+os.path.isdir solutions: I just tested on a directory with 10,000 subdirectories (with millions of files in the hierarchy below) and the performance differences are negligible. os.wal...
In Flux architecture, how do you manage Store lifecycle?
...not need to happen, and developers should strive to avoid this complexity, if possible. But the singleton Dispatcher is ready to handle it when the time comes.
Stores are singletons as well. They should remain as independent and decoupled as possible -- a self-contained universe that one can quer...
Convert objective-c typedef to its string equivalent
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This is really a C question, not specific to Objective-C (which is a superset of the C language). Enums in C are represented as integers. So you need to write a function that returns a string given an enum value. There are many ways to do this. An array of strin...
Use underscore inside Angular controllers
...om Angular code as-is.
You can also wrap it up in a service or a factory, if you'd like it to be injected:
var underscore = angular.module('underscore', []);
underscore.factory('_', ['$window', function($window) {
return $window._; // assumes underscore has already been loaded on the page
}]);
...