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ExecuteReader requires an open and available Connection. The connection's current state is Connectin
...n the Connection-Pool's territory
There's a good reason why ADO.NET internally manages the underlying Connections to the DBMS in the ADO-NET Connection-Pool:
In practice, most applications use only one or a few different
configurations for connections. This means that during application
exe...
Command to collapse all sections of code?
In Visual Studio is there a command to collapse/expand all the sections of code in a file?
20 Answers
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Speed up the loop operation in R
...Biggest problem and root of ineffectiveness is indexing data.frame, I mean all this lines where you use temp[,].
Try to avoid this as much as possible. I took your function, change indexing and here version_A
dayloop2_A <- function(temp){
res <- numeric(nrow(temp))
for (i in 1:nrow(te...
Select rows of a matrix that meet a condition
... How does this work if you don't want to specify the column names at all but want to work over all columns in the matrix?
– user5359531
Jul 22 '16 at 22:54
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CSS – why doesn’t percentage height work? [duplicate]
...s house?</p>
</div>
</div>
#inner will grow to be tall enough to contain the paragraph and #outer will grow to be tall enough to contain #inner.
When you specify the height or width as a percentage, that's a percentage with respect to the element's parent. In the case of wid...
IntelliJ and Tomcat…changed files are not automatically recognized by Tomcat
...r "Update resources" or "Update Classes and Resources"
Update resources: All changed resources (that is, all application components other than the classes) will be updated.
Update classes and resources: All changed resources will be updated; changed classes will be recompiled. Note that whether th...
Why `null >= 0 && null
... number and assigns 0 to the variable if not, where the variable is initially null or undefined .
5 Answers
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Deleting all files in a directory with Python
I want to delete all files with the extension .bak in a directory. How can I do that in Python?
7 Answers
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Similar to jQuery .closest() but traversing descendants?
...found.length) break; // At least one match: break loop
// Get all children of the current set
$currentSet = $currentSet.children();
}
return $found.first(); // Return first match of the collection
}
})(jQuery);
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What makes Scala's operator overloading “good”, but C++'s “bad”?
...t to be repeated in newer languages. Certainly, it was one feature specifically dropped when designing Java.
14 Answers
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