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How to query MongoDB with “like”?
... Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what's happening.
– Kyle Banker
J...
Setting direction for UISwipeGestureRecognizer
...Apple saying that the behavior works as was intended.
So for example in a table view you can swipe left or right in a table view cell to trigger 'delete' (this would have directions of the swipe gesture set to left and right)
This means that the original workaround is the way it's supposed to be u...
Double exclamation points? [duplicate]
... then it may not be 0 but some other falsy value. See the following truth table:
Truth Table for javascript
'' == '0' // false
0 == '' // true
0 == '0' // true
false == 'false' // false
false == '0' // true
fa...
How to load a xib file in a UIView
...
make sure check mark "also create XIB file"
I would like to perform with tableview so I choosed subclass UITableViewCell
you can choose as your requerment
XIB file desing as your wish (RestaurantTableViewCell.xib)
we need to grab the row height to set table each row hegiht
Now! need ...
how to check if object already exists in a list
...dictionary approach would be quite good assuming:
The list is relatively stable (not a lot of inserts/deletions, which dictionaries are not optimized for)
The list is quite large (otherwise the overhead of the dictionary is pointless).
If the above are not true for your situation, just use the met...
When should I really use noexcept?
...of overhead"… No, this should be implemented by not generating exception tables for such a function, which the exception dispatcher should catch and then bail out.
– Potatoswatter
May 29 '12 at 8:55
...
Creating a “logical exclusive or” operator in Java
...me result. Therefore, no need for distinct operators. The simplified truth table for a XOR operator is X ^ !X = 1. You cannot short circuit an input in XOR because you have to determine whether the inputs are different. It is a lot easier to understand if you know the fabrication of the actual XOR g...
Change a Rails application to production
...and start the migration with rake db:migrate. Make certain that a database table exists, even if you plan on adding tables later (this is also part of step 1).
RAILS_ENV=production rake secret - this will create a secret_key that you can add to config/secrets.yml . You can copy/paste this into confi...
In where shall I use isset() and !empty()
...nd the answer is:
$var = "";
var_dump(isset($var));
The type comparison tables in PHP’s manual is quite handy for such questions.
isset basically checks if a variable has any value other than null since non-existing variables have always the value null. empty is kind of the counter part to iss...
UITableViewHeaderFooterView: Unable to change background color
I'm trying to change the background color of UITableViewHeaderFooterView. Although the view is appearing, the background color remains the default color. I'm getting a log from xcode saying:
...