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Why does C++ rand() seem to generate only numbers of the same order of magnitude?
In a small application written in C/C++, I am facing a problem with the rand function and maybe the seed :
9 Answers
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How to check whether a pandas DataFrame is empty?
How to check whether a pandas DataFrame is empty? In my case I want to print some message in terminal if the DataFrame is empty.
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Difference between CTE and SubQuery?
...rsions, they are probably very similar. You would have to use the profiler and actual execution plan to spot any differences, and that would be specific to your setup (so we can't tell you the answer in full).
In general; A CTE can be used recursively; a sub-query cannot. This makes them especially...
What is the meaning of “POSIX”?
What is POSIX? I have read the Wikipedia article and I read it every time I encounter the term. The fact is that I never really understood what it is.
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Search for one value in any column of any table inside a database
...s Kondreddi
-- Site: http://vyaskn.tripod.com
-- Tested on: SQL Server 7.0 and SQL Server 2000
-- Date modified: 28th July 2002 22:50 GMT
CREATE TABLE #Results (ColumnName nvarchar(370), ColumnValue nvarchar(3630))
SET NOCOUNT ON
DECLARE @TableName nvarchar(256), @ColumnName nvarchar(128), @Sear...
Entity Attribute Value Database vs. strict Relational Model Ecommerce
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There's a few general pros and cons I can think of, there are situations where one is better than the other:
Option 1, EAV Model:
Pro: less time to design and develop a simple application
Pro: new entities easy to add (might even
be added by users?)...
How to change column datatype in SQL database without losing data
I have SQL Server database and I just realized that I can change the type of one of the columns from int to bool .
11 A...
How do I create and read a value from cookie?
How can I create and read a value from a cookie in JavaScript?
19 Answers
19
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Can I bind an array to an IN() condition?
...right. fixed the code (didn't test it though)
edit: both chris (comments) and somebodyisintrouble suggested that the foreach-loop ...
(...)
// bindvalue is 1-indexed, so $k+1
foreach ($ids as $k => $id)
$stmt->bindValue(($k+1), $id);
$stmt->execute();
... might be redundant, so the...
How to map and remove nil values in Ruby
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Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simp...