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What is the most efficient/elegant way to parse a flat table into a tree?
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Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentI...
Options, Settings, Properties, Configuration, Preferences — when and why?
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Tricky, this, as there's no one single consistent style followed by all applications. As you say they are (broadly) synonyms.
In truth it doesn't really matter so long as your expected audience understands what you mean.
The biggest difference is between Properties, which usually affect a c...
Viewing all defined variables [duplicate]
...ython shell. What I want to have is Matlab style listout where you can see all the variables that have been defined up to a point (so I know which names I've used, their values and such).
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One DbContext per web request… why?
...the DbContext caches data, it gets stale pretty soon. This will get you in all sorts of trouble when multiple users/applications work on that database simultaneously (which is very common of course). But I expect you already know that and just want to know why not to just inject a new instance (i.e....
How can I check the system version of Android?
...ow how can I check the system version (e.g. 1.0 , 2.2 , etc.) programatically?
13 Answers
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How to initialize all members of an array to the same value?
... array in C (not C++ if that makes a difference). I want to initialize all members of the same value.
23 Answers
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What are Java command line options to set to allow JVM to be remotely debugged?
...ave this article bookmarked on setting this up for Java 5 and below.
Basically run it with:
-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=1044
For Java 5 and above, run it with:
-agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=1044
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Getting rid of \n when using .readlines() [duplicate]
...string:
for i in contents:
alist.append(i.rstrip('\n'))
This leaves all other whitespace intact. If you don't care about whitespace at the start and end of your lines, then the big heavy hammer is called .strip().
However, since you are reading from a file and are pulling everything into mem...
How does __proto__ differ from constructor.prototype?
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I've been trying to wrap my head around this recently and finally came up with this "map" that I think sheds full light over the matter
http://i.stack.imgur.com/KFzI3.png
I know I'm not the first one making this up but it was more interesting figuring it out that finding it :-). An...
Relative imports in Python 2.7
... not determine what package Python thinks it is in. That depends, additionally, on how you load the file into Python (by running or by importing).
There are two ways to load a Python file: as the top-level script, or as a
module. A file is loaded as the top-level script if you execute it directl...