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How to get year/month/day from a date object?
...
info
If a 2 digit month and date is desired (2016/01/01 vs 2016/1/1)
code
var dateObj = new Date();
var month = ('0' + (dateObj.getMonth() + 1)).slice(-2);
var date = ('0' + dateObj.getDate()).slice(-2);
var year = dateObj.getFullYear();
var shortDate = year + '/' + month + '/' ...
Is there a “not equal” operator in Python?
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Not equal != (vs equal ==)
Are you asking about something like this?
answer = 'hi'
if answer == 'hi': # equal
print "hi"
elif answer != 'hi': # not equal
print "no hi"
This Python - Basic Operators chart might be helpful.
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Is the C# static constructor thread safe?
... {
mutex.WaitOne();
return instance;
}
// Each call to Acquire() requires a call to Release()
public static void Release()
{
mutex.ReleaseMutex();
}
}
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Why is parenthesis in print voluntary in Python 2.7?
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In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between...
Is there a performance impact when calling ToList()?
...on) constructor. This constructor must make a copy of the array (more generally IEnumerable<T>), otherwise future modifications of the original array will change on the source T[] also which wouldn't be desirable generally.
I would like to reiterate this will only make a difference with a hu...
What's a correct and good way to implement __hash__()?
...be integers, and there aren't too many of them, I suppose you could potentially run slightly faster with some home-rolled hash, but it likely wouldn't be as well distributed. hash((self.attr_a, self.attr_b, self.attr_c)) is going to be surprisingly fast (and correct), as creation of small tuples is ...
Django 1.7 - makemigrations not detecting changes
... may happen due to the following reasons:
You did not add the app in INSTALLED_APPS list in settings.py
(You have to add either the app name or the dotted path to the subclass of AppConfig in apps.py in the app folder, depending on the version of django you are using). Refer documentation: INST...
How to copy a row and insert in same table with a autoincrement field in MySQL?
....)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SELECT:
insert into your_table (id, c1, c2, ...)
select 2, c1, c2, ...
from your_table
where i...
Adding a new value to an existing ENUM Type
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It's worth mentioning that this can all be done in a single transaction, so it's mostly safe to do it in a production database.
– David Leppik
Jul 8 '11 at 20:41
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Case insensitive searching in Oracle
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Since 10gR2, Oracle allows to fine-tune the behaviour of string comparisons by setting the NLS_COMP and NLS_SORT session parameters:
SQL> SET HEADING OFF
SQL> SELECT *
2 FROM NLS_SESSION_PARAMETERS
3 WHERE PARAMETER IN ('NLS_COMP', ...