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Why do variable names often start with the letter 'm'? [duplicate]
Looking at the Android tutorials such as the Notepad tutorial , I noticed that almost all variables are named starting with the letter 'm'. What convention is this, and where does it originate from?
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Finding duplicate values in a SQL table
...T(*) > 1
Simply group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of "functional dependency":
In relational database theory, a functional dependency is a constraint between two sets of attrib...
Convert hex string to int in Python
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x = int("deadbeef", 16)
With the 0x prefix, Python can distinguish hex and decimal automatically.
>>> print int("0xdeadbeef", 0)
3735928559
>>> print int("10", 0)
10
(You must specify 0 as the base in order to invoke this prefix-guessing behavior; omitting the second paramet...
iOS - Dismiss keyboard when touching outside of UITextField
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You'll need to add an UITapGestureRecogniser and assign it to the view, and then call resign first responder on the UITextField on it's selector.
The code:
In viewDidLoad
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@select...
Check whether a string is not null and not empty
How can I check whether a string is not null and not empty?
31 Answers
31
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iPhone Simulator - Simulate a slow connection?
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awesome just tried that out and it does the business. Thanks!
– Max MacLeod
Apr 17 '12 at 14:00
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What is best tool to compare two SQL Server databases (schema and data)? [duplicate]
...ike to compare two SQL Server databases including schema (table structure) and data in tables too. What is best tool to do this?
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python date of the previous month
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datetime and the datetime.timedelta classes are your friend.
find today.
use that to find the first day of this month.
use timedelta to backup a single day, to the last day of the previous month.
print the YYYYMM string you're looki...
How can I get the timezone name in JavaScript?
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The Internationalization API supports getting the user timezone, and is supported in all current browsers.
console.log(Intl.DateTimeFormat().resolvedOptions().timeZone)
Keep in mind that on some older browser versions that support the Internationalization API, the timeZone prop...
Iterating each character in a string using Python
...for loop construct,
for example, open("file.txt") returns a file object (and opens the file), iterating over it iterates over lines in that file
with open(filename) as f:
for line in f:
# do something with line
If that seems like magic, well it kinda is, but the idea behind it is re...