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Fast way to discover the row count of a table in PostgreSQL
...of rows due to the nature of MVCC. There is a way to speed this up dramatically if the count does not have to be exact like it seems to be in your case.
Instead of getting the exact count (slow with big tables):
SELECT count(*) AS exact_count FROM myschema.mytable;
You get a close estimate like ...
Change multiple files
...ot even just a builtin. For sed -i 's/old/new' *, the expansion of * must ALL be passed as an arglist to sed, and I'm fairly sure this has to happen before the sed process can even be started. Using the for loop, the full arglist (the expansion of *) never gets passed as a command, only stored in ...
How to make an Android Spinner with initial text “Select One”?
I want to use a Spinner that initially (when the user has not made a selection yet) displays the text "Select One". When the user clicks the spinner, the list of items is displayed and the user selects one of the options. After the user has made a selection, the selected item is displayed in the Spi...
How to create a GUID/UUID in Python
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Also, have a look at the shortuuid module I wrote, as it allows you to generate shorter, readable UUIDs: github.com/stochastic-technologies/shortuuid
– Stavros Korokithakis
Dec 31 '12 at 16:22
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Remove scrollbar from iframe
...t work because the overflow happens in the iframe document, which you generally won't be able to modify because of cross-domain iframe security restrictions.
– thdoan
Apr 17 '15 at 11:09
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Linux error while loading shared libraries: cannot open shared object file: No such file or director
...nk the most frequent cause of these sorts of message is because you've installed a package, but not installed the "-dev" version of that package.
Well, it's not lying - there is no libpthread_rt.so.1 in that listing. You probably need to re-configure and re-build it so that it depends on the li...
How to determine when a Git branch was created?
... master`
If you’d rather see it in context using gitk, then use
gitk --all --select-commit=`git merge-base foo master`
(where foo is the name of the branch you are looking for.)
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Haskell: How is pronounced? [closed]
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Sorry, I don't really know my math, so I'm curious how to pronounce the functions in the Applicative typeclass
Knowing your math, or not, is largely irrelevant here, I think. As you're probably aware, Haskell borrows a few bits of terminolo...
How to write a foreach in SQL Server?
...d
FETCH NEXT FROM MY_CURSOR INTO @PractitionerId
END
CLOSE MY_CURSOR
DEALLOCATE MY_CURSOR
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Why is lock(this) {…} bad?
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It is bad form to use this in lock statements because it is generally out of your control who else might be locking on that object.
In order to properly plan parallel operations, special care should be taken to consider possible deadlock situations, and having an unknown number of lock en...