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Properly escape a double quote in CSV
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I know this is an old post, but here's how I solved it (along with converting null values to empty string) in C# using an extension method.
Create a static class with something like the following:
/// <summary>
/// Wraps value in quotes if necessary and converts nulls to empt...
Best way to repeat a character in C#
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string.Concat(Enumerable.Repeat("ab", 2));
Returns
"abab"
And
string.Concat(Enumerable.Repeat("a", 2));
Returns
"aa"
from...
Is there a built-in function to repeat string or char in .net?
share
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Why malloc+memset is slower than calloc?
...se it can skip memset() entirely. In other cases, calloc() can even cheat and not allocate any memory! However, malloc()+memset() will always do the full amount of work.
Understanding this requires a short tour of the memory system.
Quick tour of memory
There are four main parts here: your prog...
How to change the default collation of a table?
...set and collation of a table including those of existing columns (note the convert to clause):
alter table <some_table> convert to character set utf8mb4 collate utf8mb4_unicode_ci;
Edited the answer, thanks to the prompting of some comments:
Should avoid recommending utf8. It's almost n...
What are the options for storing hierarchical data in a relational database? [closed]
... thought I'd give Celko a bit of competition by coming up with a method to convert an Adjacency List to Nested sets at speeds that just seem impossible. Here's the performance of the push stack method on my i5 laptop.
Duration for 1,000 Nodes = 00:00:00:870
Duration for 10,000 Nodes = 00:01...
How do I suspend painting for a control and its children?
...ke to completely prevent it from redrawing while I do that - SuspendLayout and ResumeLayout aren't enough. How do I suspend painting for a control and its children?
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For loop example in MySQL
...ile v_counter < v_max do
insert into foo (val) values ( floor(0 + (rand() * 65535)) );
set v_counter=v_counter+1;
end while;
commit;
end #
delimiter ;
call load_foo_test_data();
select * from foo order by id;
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How do I define a method in Razor?
...cality. MVC isn't the only game in town. Some folks just like simple razor and URLRewrite as MVC is a lot to do for little benefit IMO
– Jason Sebring
Oct 28 '12 at 18:00
5
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How to return result of a SELECT inside a function in PostgreSQL?
...ple.
But note the potential naming conflict between the OUT parameter cnt and the column alias of the same name. In this particular case (RETURN QUERY SELECT ...) Postgres uses the column alias over the OUT parameter either way. This can be ambiguous in other contexts, though. There are various way...
How is std::function implemented?
...ed by the compiler creating a class with overloaded function call operator and the referenced variables as members. This suggests that the size of lambda expressions varies, and given enough references variables that size can be arbitrarily large .
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