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Why are joins bad when considering scalability?
...spreading out, or paring down the repeated work to the bare essentials, in order to minimize resource use per work unit. To scale well, you don't do anything you don't need to in volume, and the things you actually do you make sure are done as efficiently as possible.
In that context, of course join...
Function in JavaScript that can be called only once
...
Accordingly to asawyer's response, you only needed to do _.once(foo) or _.once(bar), and the functions themselves don't need to be aware of being ran only once (no need for the noop and no need for the * = noop).
– fableal
Oct 3 '12 at 17:31
...
How to export all collections in MongoDB?
...
For lazy people, use mongodump, it's faster:
mongodump -d <database_name> -o <directory_backup>
And to "restore/import" it (from directory_backup/dump/):
mongorestore -d <database_name> <directory_backup>
This way, you don't need to deal with all collections individ...
How do I change the color of the text in a UIPickerView under iOS 7?
...spaced 35 pts apart for a picker height of 180.
Swift 3:
func pickerView(_ pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? {
let string = "myString"
return NSAttributedString(string: string, attributes: [NSForegroundColorAtt...
How to use count and group by at the same select statement
...
If you want to order by count (sound simple but i can`t found an answer on stack of how to do that) you can do:
SELECT town, count(town) as total FROM user
GROUP BY town ORDER BY total DESC
...
Range references instead values
...{
field string
}
func main() {
var array [10]MyType
for idx, _ := range array {
array[idx].field = "foo"
}
for _, e := range array {
fmt.Println(e.field)
fmt.Println("--")
}
}
...
Python 3 ImportError: No module named 'ConfigParser'
...s very buggy, it crashes at first execute call.
– if __name__ is None
Dec 30 '12 at 14:46
15
@Jan...
How to Iterate over a Set/HashSet without an Iterator?
...therwise specified by the implementing class, actions are performed in the order of iteration (if an iteration order is specified). Exceptions thrown by the action are relayed to the caller. Implementation Requirements:
The default implementation behaves as if:
for (T t : this)
action.accept...
C# “internal” access modifier when doing unit testing
...Include="System.Runtime.CompilerServices.InternalsVisibleTo">
<_Parameter1>MyTests</_Parameter1>
</AssemblyAttribute>
</ItemGroup>
Or if you have one test project per project to be tested, you could do something like this in your Directory.Build.props file:
&l...
How to delete all Annotations on a MKMapView
...me with copy and paste and removing [locs release] and changing mapView to _mapView. I was following a great tutorial for MKDirections here devfright.com/mkdirections-tutorial and wanted to remove the pin after getting directions. I added the code below the last line of that method to the 'clear rou...