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MYSQL OR vs IN performance
... not believe people who give their "opinion", science is all about testing and evidence.
I ran a loop of 1000x the equivalent queries (for consistency, I used sql_no_cache):
IN: 2.34969592094s
OR: 5.83781504631s
Update:
(I don't have the source code for the original test, as it was 6 years ago, ...
Oracle SQL: Update a table with data from another table
...ere is no matching row in t2. Without it, every row in t1 will be updated and the values will be set to NULL if there is no matching row in t2. That is generally not what you want to happen so the WHERE EXISTS is generally needed.
– Justin Cave
Aug 5 '13 at 1...
Python extract pattern matches
...need to capture from regex. search for the pattern, if found, retrieve the string using group(index). Assuming valid checks are performed:
>>> p = re.compile("name (.*) is valid")
>>> result = p.search(s)
>>> result
<_sre.SRE_Match object at 0x10555e738>
>>>...
Significance of bool IsReusable in http handler interface
...nt by “context switch”. If you access things from the sesson or query string (content.Request.QueryString) is that reusable or not?
– zod
Jun 9 '11 at 12:37
5
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Difference between StringBuilder and StringBuffer
What is the main difference between StringBuffer and StringBuilder ?
Is there any performance issues when deciding on any one of these?
...
How to access command line parameters?
... functions return an iterator over the arguments. The former iterates over Strings (that are easy to work with) but panics if one of the arguments is not valid unicode. The latter iterates over OsStrings and never panics.
Note that the first element of the iterator is the name of the program itself...
Remove empty elements from an array in Javascript
...d on what you consider to be "empty" for example, if you were dealing with strings, the above function wouldn't remove elements that are an empty string.
One typical pattern that I see often used is to remove elements that are falsy, which include an empty string "", 0, NaN, null, undefined, and fa...
Explicitly set Id with Doctrine when using “AUTO” strategy
...
Thank you and I'm happy to help a bit as I can :)
– nicolasbui
Dec 5 '12 at 18:20
2
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What does flushing the buffer mean?
...ing cin flushes cout so you don't need an explicit flush to do this:
std::string colour;
std::cout << "Enter your favourite colour: ";
std::cin >> colour;
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Python module os.chmod(file, 664) does not change the permission to rw-rw-r— but -w--wx----
...
If you have desired permissions saved to string then do
s = '660'
os.chmod(file_path, int(s, base=8))
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