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PostgreSQL: Difference between text and varchar (character varying)
...able length array).
Check this article from Depesz: http://www.depesz.com/index.php/2010/03/02/charx-vs-varcharx-vs-varchar-vs-text/
A couple of highlights:
To sum it all up:
char(n) – takes too much space when dealing with values shorter than n (pads them to n), and can lead to subt...
Can I set enum start value in Java?
...va to create a enum of sequential integers (similar to a C++ enum), for an index into an array or something, be to write: enum Ids { NAME(0), AGE(1), HEIGHT(2), WEIGHT(3); } Thank you, -bn
– bn.
Aug 13 '09 at 19:35
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How can I git stash a specific file?
...
@JamesJohnston git stash --keep-index will allow you to stash all the unstaged changes (the opposite of what you're looking for). stackoverflow.com/a/8333163/378253
– Nicolas Wormser
Oct 16 '13 at 11:23
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See changes to a specific file using git
... is a short value. For example, to find out who changed foo to bar in dist/index.php, you would use git blame dist/index.php | grep bar
– Kraang Prime
May 11 '17 at 15:38
add ...
Error message “Forbidden You don't have permission to access / on this server” [closed]
... answer instead
Many scenarios can lead to 403 Forbidden:
A. Directory Indexes (from mod_autoindex.c)
When you access a directory and there is no default file found in this directory
AND Apache Options Indexes is not enabled for this directory.
A.1. DirectoryIndex option example
DirectoryInde...
What is the difference between static_cast and C style casting?
... and what C-style cast really does: https://anteru.net/blog/2007/12/18/200/index.html
C-Style casting, using the (type)variable syntax. The worst ever
invented. This tries to do the following casts, in this order: (see
also C++ Standard, 5.4 expr.cast paragraph 5)
const_cast
static...
Rails find_or_create_by more than one attribute?
...Optimization tip: regardless of which solution you choose, consider adding indexes for the attributes you are querying most frequently.
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How to dynamically compose an OR query filter in Django?
From an example you can see a multiple OR query filter:
13 Answers
13
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Best database field type for a URL
...ome up with a uri datatype that "understands" the structure of uri so that indexing and search is done efficiently, like oracle did...wait, mysql is now oracle's... download.oracle.com/docs/cd/B10464_05/web.904/b12099/…
– redben
Mar 26 '11 at 14:20
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How can I calculate the number of lines changed between two commits in git?
... as well (without parameters it compares the working directory against the index). E.g.
git diff --stat HEAD^ HEAD
to compare the parent of HEAD with HEAD.
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