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How to iterate over values of an Enum having flags?
...s)Enum.Parse(typeof(Items), v)); // Boo
I adapted what Enum does internally to generate the string to instead return the flags. You can look at the code in reflector and should be more or less equivalent. Works well for general use cases where there are values which contain multiple bits.
sta...
What exactly is Python's file.flush() doing?
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There's typically two levels of buffering involved:
Internal buffers
Operating system buffers
The internal buffers are buffers created by the runtime/library/language that you're programming against and is meant to speed things up by ...
Create a CSS rule / class with jQuery at runtime
Usually I have a CSS file which has the following rule:
21 Answers
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Select by partial string from a pandas DataFrame
...egex search is not required, so specify regex=False to disable it.
#select all rows containing "foo"
df1[df1['col'].str.contains('foo', regex=False)]
# same as df1[df1['col'].str.contains('foo')] but faster.
col
0 foo
1 foobar
Performance wise, regex search is slower than substring s...
How do you clear a slice in Go?
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It all depends on what is your definition of 'clear'. One of the valid ones certainly is:
slice = slice[:0]
But there's a catch. If slice elements are of type T:
var slice []T
then enforcing len(slice) to be zero, by the a...
How to request a random row in SQL?
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-1 for relying on order by rand() or equivalents in all dbs :|. also mentioned here.
– AD7six
May 26 '14 at 9:27
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Remove duplicate rows in MySQL
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A really easy way to do this is to add a UNIQUE index on the 3 columns. When you write the ALTER statement, include the IGNORE keyword. Like so:
ALTER IGNORE TABLE jobs
ADD UNIQUE INDEX idx_name (site_id, title, company);
Th...
How to track down log4net problems
I use log4net all the time, but one thing I've never figured out is how to tell what's going on on the inside. For example, I've got a console appender and a database appender in my project. I made a few changes to the database and the code, and now the database appender doesn't work anymore. I'll f...
html (+css): denoting a preferred place for a line break
... Text </span>
it will wrap first in preferred blocks and then in smaller fragments as needed.
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Database design for a survey [closed]
...ring what would be the best way to implement this in the database, specifically the tables required. The survey contains different types of questions. For example: text fields for comments, multiple choice questions, and possibly questions that could contain more than one answer (i.e. check all that...