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How do SO_REUSEADDR and SO_REUSEPORT differ?
...BSD socket implementation is the mother of all socket implementations. Basically all other systems copied the BSD socket implementation at some point in time (or at least its interfaces) and then started evolving it on their own. Of course the BSD socket implementation was evolved as well at the sam...
When should iteritems() be used instead of items()?
... D(dict(a=1, b=2, c=3))
>>> [v for v in d]
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: __iter__ returned non-iterator of type 'list'
The same is true for viewitems, which is available in Python 3.
Also, since items returns a copy of the...
Can a foreign key be NULL and/or duplicate?
.... So your proposal table would have two foreign keys, one with the client ID and one with the sales rep ID. However, at the time the record is created, a sales rep is not always assigned (because no one is free to work on it yet), so the client ID is filled in but the sales rep ID might be null. ...
Select random row from a sqlite table
...extend this solution to a join? When using SELECT a.foo FROM a JOIN b ON a.id = b.id WHERE b.bar = 2 ORDER BY RANDOM() LIMIT 1; I always get the same row.
– Helmut Grohne
Sep 19 '13 at 8:18
...
Android read text raw resource file
...ered Apr 15 '11 at 11:22
VovodroidVovodroid
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SQL Server indexes - ascending or descending, what difference does it make?
...y Optimiser's point of view.
For the table definition
CREATE TABLE T1( [ID] [int] IDENTITY NOT NULL,
[Filler] [char](8000) NULL,
PRIMARY KEY CLUSTERED ([ID] ASC))
The Query
SELECT TOP 10 *
FROM T1
ORDER BY ID DESC
Uses an ordered scan with scan direction BAC...
MySQL Multiple Joins in one query?
... dashboard_data.headline, dashboard_data.message, dashboard_messages.image_id, images.filename
FROM dashboard_data
INNER JOIN dashboard_messages
ON dashboard_message_id = dashboard_messages.id
INNER JOIN images
ON dashboard_messages.image_id = images.image_id
However be ...
Where does Console.WriteLine go in ASP.NET?
...d inside a TextWriter), which is a dummy implementation of Stream that basically ignores all input, and gives no output.
So it is conceptually equivalent to /dev/null, but the implementation is more streamlined: there's no actual I/O taking place with the null device.
Also, apart from calling SetO...
Logger slf4j advantages of formatting with {} instead of string concatenation
...nd should be avoided if possible, as the {} allows delaying the toString() call and string construction to after it has been decided if the event needs capturing or not. By having the logger format a single string the code becomes cleaner in my opinion.
You can provide any number of arguments. Not...
Python argparse mutual exclusive group
...nd line wrapper for querying a mongodb. The collection instance can either call the method aggregate or the method find with to optional arguments query and fields, hence you see why the first two arguments are compatible and the last one isn't.
So now I run parser.parse_args() and check it's cont...