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Why does the MongoDB Java driver use a random number generator in a conditional?
...hat this piece of code amounts to
if (!_ok && Math.random() <= 0.1)
return res;
The commit that originally introduced this logic had
if (_ok == true) {
_logger.log( Level.WARNING , "Server seen down: " + _addr, e );
} else if (Math.random() < 0.1) {
_logger.log( Level.WARNING ...
Python `if x is not None` or `if not x is None`?
...
1029
There's no performance difference, as they compile to the same bytecode:
Python 2.6.2 (r262:7...
how do you filter pandas dataframes by multiple columns
...sub-statements with ():
males = df[(df[Gender]=='Male') & (df[Year]==2014)]
To store your dataframes in a dict using a for loop:
from collections import defaultdict
dic={}
for g in ['male', 'female']:
dic[g]=defaultdict(dict)
for y in [2013, 2014]:
dic[g][y]=df[(df[Gender]==g) & ...
Entity Framework - Start Over - Undo/Rollback All Migrations
... to rollback all migrations you can use:
Update-Database -TargetMigration:0
or equivalent:
Update-Database -TargetMigration:$InitialDatabase
In some cases you can also delete database and all migration classes.
share
...
Use NUnit Assert.Throws method or ExpectedException attribute?
...actice?
– SamuelDavis
Feb 22 '13 at 0:03
5
@SamuelDavis - in general you wouldn't want to test di...
How do you rename a table in SQLite 3.0?
How do you rename a table in SQLite 3.0?
2 Answers
2
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PowerShell script not accepting $ (dollar) sign
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answered Oct 23 '09 at 18:23
Shankar R10NShankar R10N
4,42811 gold badge1818 silver badges2424 bronze badges
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Alter column, add default constraint
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answered Jan 19 '10 at 17:07
SQLMenaceSQLMenace
122k2323 gold badges194194 silver badges218218 bronze badges
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Regular expression for a string that does not start with a sequence
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edited May 22 '09 at 20:05
answered May 22 '09 at 18:57
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Sending “User-agent” using Requests library in Python
...requests
url = 'SOME URL'
headers = {
'User-Agent': 'My User Agent 1.0',
'From': 'youremail@domain.com' # This is another valid field
}
response = requests.get(url, headers=headers)
If you're using requests v2.12.x and older
Older versions of requests clobbered default headers, so you...