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Is there any difference between GROUP BY and DISTINCT
...hat the two operations "happen" at two very different steps in the logical order of operations that are executed in a SELECT statement.
Here are the most important operations:
FROM (including JOIN, APPLY, etc.)
WHERE
GROUP BY (can remove duplicates)
Aggregations
HAVING
Window functions
SELECT
DI...
Can modules have properties the same way that objects can?
...
I would do this in order to properly inherit all the attributes of a module, and be correctly identified by isinstance()
import types
class MyModule(types.ModuleType):
@property
def y(self):
return 5
>>> a=MyModule(...
How to sort an array in descending order in Ruby
...; while (--len > 0); is copying the pointers to the elements in reverse order if I remember my C correctly, so the array is reversed.
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How to disable typing special characters when pressing option key in Mac OS X? [closed]
...ion-b a red colored key - meaning it's a dead key. Double clicking it will allow you to change it from a dead key to an output key. When prompted for the output you can put in the same thing (by pressing Option-b).
Thus it will output the same character but will not be considered a dead key, so In...
Grep for literal strings
...le, as part of a line in a seperate log file. The search text can contain all sorts of regex special characters, e.g., []().*^$-\ .
...
Using Auto Layout in UITableView for dynamic cell layouts & variable row heights
...ll to grow in height. (Of course, you need to get the constraints right in order for this to work correctly!)
Getting your constraints right is definitely the hardest and most important part of getting dynamic cell heights working with Auto Layout. If you make a mistake here, it could prevent every...
back button callback in navigationController in iOS
...IBarButtonItem alloc] initWithTitle:@”back”
style:UIBarButtonItemStyleBordered
target:self
action:@selector(handleBack:)];
self.navigationItem.leftBarButtonItem = backButton;
[backButton release];
}
- (void) handleBack:(id)sender
{
// pop to root view controller
[self.navigationController popT...
How to make URL/Phone-clickable UILabel?
... }
})
}}
This class was made by reusing code from this answer. In order to make attributed strings check out this answer. And here you can find how to make phone urls.
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Testing Abstract Classes
...ted, you need means to UT the concrete methods of abstract classes.
Personally, I use PHPUnit, and it has so called stubs and mock objects to help you testing this kind of things.
Straight from PHPUnit manual:
abstract class AbstractClass
{
public function concreteMethod()
{
retur...
Checking if a field contains a string
I'm looking for an operator, which allows me to check, if the value of a field contains a certain string.
10 Answers
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