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What are the pros and cons of performing calculations in sql vs. in your application
...lations like SUM(), AVG(),MIN(), MAX() here the database engine will be an order of magnitude faster than a Java implementation.
Anywhere the calculation is used to filter rows. Filtering at the DB is much more efficient than reading a row and then discarding it.
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Why is it faster to check if dictionary contains the key, rather than catch the exception in case it
...ng exceptions is inherently expensive, because the stack has to be unwound etc.
On the other hand, accessing a value in a dictionary by its key is cheap, because it's a fast, O(1) operation.
BTW: The correct way to do this is to use TryGetValue
obj item;
if(!dict.TryGetValue(name, out item))
r...
How to make pipes work with Runtime.exec()?
...u can also do something like this:
String[] cmd = {
"/bin/sh",
"-c",
"ls /etc | grep release"
};
Process p = Runtime.getRuntime().exec(cmd);
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How to check if the string is empty?
...ould also enter the if not myString: block if myString were None, 0, False etc. So if you aren't sure what type myString is, you should use if myString == "": to determine if it is an empty string as opposed to some other falsy value.
– Andrew Clark
Aug 7 '13 ...
Protected in Interfaces
...s: So much of OOP is about properly structuring objects, classes, packages etc., if a programmer has a hard time with doing all that properly, he has a much bigger problem. Java was built for that type of thing.
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Move the most recent commit(s) to a new branch with Git
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Is the order of cherry picking important?
– kon psych
Apr 23 '15 at 22:04
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What is git actually doing when it says it is “resolving deltas”?
...on't want to have to play back every single change ever on a given file in order to get the current version, so Git also has occasional snapshots of the file contents stored as well. "Resolving deltas" is the step that deals with making sure all of that stays consistent.
Here's a chapter from the "...
Android: allow portrait and landscape for tablets, but force portrait on phone?
...ically) will behave like normal, based on sensor and user-locked rotation, etc. Everything else (phones, pretty much) will be portrait only.
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ruby system command check exit code
...formation from this object, including: status code, execution status, pid, etc.
Some useful methods of the $? object:
$?.exitstatus => return error code
$?.success? => return true if error code is 0, otherwise false
$?.pid => created process pid
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Parse email content from quoted reply
...d the thread, you can then remove the external text (such as To, From, CC, etc... lines) and you're done.
If the messages you are working with do not have the headers, you can also use similarity matching to determine what parts of an email are the reply text. In this case you're stuck with doin...