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What is a “Bitmap heap scan” in a query plan?
... stay in memory, but you get the point).
A bitmap index scan will sequentially open a short-list of disk pages, and grab every applicable row in each one (hence the so-called recheck cond you see in query plans).
Note, as an aside, how clustering/row order affects the associated costs with either ...
How is the java memory pool divided?
...ap memory
The heap memory is the runtime data area from which the Java VM allocates memory for all class instances and arrays. The heap may be of a fixed or variable size. The garbage collector is an automatic memory management system that reclaims heap memory for objects.
Eden Space: The pool fr...
Looping over a list in Python
I have a list with sublists in it. I want to print all the sublists with length equal to 3.
4 Answers
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How to “re-run with -deprecation for details” in sbt?
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> compile
> exit
Due to in ThisBuild, set applies the settings to all sub-projects, as well.
Command Line
You could also run the above as a single command on command line.
sbt '; set scalacOptions in ThisBuild ++= Seq("-unchecked", "-deprecation") ; compile'
The trick is to use ; (sem...
Remove menu and status bars in TinyMCE 4
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Small typo: menuBar: 'file edit' should be menubar: 'file edit'
– Cory Mawhorter
May 27 '13 at 9:49
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ipython notebook clear cell output in code
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Using the clear_output(wait=True) will generally make the result nicer if you have clear_output inside a loop.
– Toke Faurby
Jun 8 '17 at 23:49
1
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SQL - many-to-many table primary key
...at the table sorted, just the index. And the index won't be stored sequentially, it'll be stored in an efficient manner to be able to be retrieved quickly.
In addition, the vast majority of database tables are read far more often than written. That makes anything you do on the select side far more ...
How to remove illegal characters from path and filenames?
...gal path into a legitimate but probably unintended one.
Edit: Or a potentially 'better' solution, using Regex's.
string illegal = "\"M\"\\a/ry/ h**ad:>> a\\/:*?\"| li*tt|le|| la\"mb.?";
string regexSearch = new string(Path.GetInvalidFileNameChars()) + new string(Path.GetInvalidPathChars());
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RSpec controller testing - blank response.body
...with a problem when testing my controllers with RSpec - the response.body call always returns an empty string. In browser everything renders correctly, and cucumber feature tests seem to get it right, but RSpec fails each and every time.
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'printf' vs. 'cout' in C++
...letely on operator overloading, so there is no issue with custom formats - all you do is define a subroutine taking std::ostream as the first argument and your type as second. As such, there are no namespace problems - as long you have a class (which isn't limited to one character), you can have wor...