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Chaining multiple filter() in Django, is this a bug?
I always assumed that chaining multiple filter() calls in Django was always the same as collecting them in a single call.
4...
Throw an error in a MySQL trigger
...e SIGNAL syntax to throw an exception:
signal sqlstate '45000' set message_text = 'My Error Message';
State 45000 is a generic state representing "unhandled user-defined exception".
Here is a more complete example of the approach:
delimiter //
use test//
create table trigger_test
(
id int...
Fastest way to find second (third…) highest/lowest value in vector or column
R offers max and min, but I do not see a really fast way to find another value in the order, apart from sorting the whole vector and then picking a value x from this vector.
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What are the main purposes of using std::forward and which problems it solves?
... references. What is the purpose of doing that? How would that affect the called function inner if we leave t1 & t2 as lvalues?
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data.frame rows to a list
...ts in your list are atomic vectors, not list as the OP requested. It is usually not a problem until your xy.df contains mixed types...
– Calimo
Feb 28 '14 at 14:40
2
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Replace a newline in TSQL
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Actually a new line in a SQL command or script string can be any of CR, LF or CR+LF. To get them all, you need something like this:
SELECT REPLACE(REPLACE(@str, CHAR(13), ''), CHAR(10), '')
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Listing all permutations of a string/integer
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First of all: it smells like recursion of course!
Since you also wanted to know the principle, I did my best to explain it human language. I think recursion is very easy most of the times. You only have to grasp two steps:
The first ...
How to load a tsv file into a Pandas DataFrame?
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
Configuring IntelliJ IDEA for unit testing with JUnit
I decided to try out IntelliJ this morning via the trial version and installed the JUnit plugin. I made a new Java project and I want to write a test case for it.
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What is a Y-combinator? [closed]
...m the “functional” side of things. Most programmers don't know much at all about combinators, if they've even heard about them.
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