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JOIN queries vs multiple queries
...ase. It depends on a lot of things. Jeff Atwood (founder of this site) actually wrote about this. For the most part, though, if you have the right indexes and you properly do your JOINs it is usually going to be faster to do 1 trip than several.
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Correct way to use StringBuilder in SQL
... of using StringBuilder, i.e reducing memory. Is it achieved?
No, not at all. That code is not using StringBuilder correctly. (I think you've misquoted it, though; surely there aren't quotes around id2 and table?)
Note that the aim (usually) is to reduce memory churn rather than total memory used...
How to install PostgreSQL's pg gem on Ubuntu?
I'm trying to install PostgreSQL's pg gem for Ruby.
19 Answers
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Which “href” value should I use for JavaScript links, “#” or “javascript:void(0)”?
...evelopers inevitably leads to some using the return value of the function called like this:
function doSomething() {
//Some code
return false;
}
But then they forget to use return doSomething() in the onclick and just use doSomething().
A second reason for avoiding # is that the final re...
Is there a way to get rid of accents and convert a whole string to regular letters?
...f accents and making those letters regular apart from using String.replaceAll() method and replacing letters one by one?
Example:
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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
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If you're actually dealing with 1-dimensional arrays (like in you're example) then on you're first line use a Series instead of a DataFrame, like @DSM used: df = pd.Series({'countries':['US','UK','Germany','China']})
–...
How to preview git-pull without doing fetch?
...EAD...origin/master (three dots not two) to show a single diff.
There normally isn't any need to undo a fetch, because doing a fetch only updates the remote branches and none of your branches. If you're not prepared to do a pull and merge in all the remote commits, you can use git cherry-pick to ac...
How to fix “Referenced assembly does not have a strong name” error?
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To avoid this error you could either:
Load the assembly dynamically, or
Sign the third-party assembly.
You will find instructions on signing third-party assemblies in .NET-fu: Signing an Unsigned Assembly (Without Delay Signing).
Signing Third-Party Assemblies
The basic principle t...
Skip List vs. Binary Search Tree
... Fraser and Harris's latest paper Concurrent programming without locks. Really good stuff if you're interested in lock-free data structures. The paper focuses on Transactional Memory and a theoretical operation multiword-compare-and-swap MCAS. Both of these are simulated in software as no hardwar...
Java: How to Indent XML Generated by Transformer
... out the resulting XML. The problem is that it isn't indenting the text at all despite having set the parameter "indent" explicitly.
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