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What is the difference between an ORM and an ODM?
I am trying to figure out what the difference is between ORM and ODM, as far as I understand the concept, ORM (Object Relational Mapper) maps the relations between data, where as ODM (Object Document Mapper) deals with documents. Am I right in assuming that mySQL is an example of ORM and MongoDB is ...
Always pass weak reference of self into block in ARC?
...am a little confused about block usage in Objective-C. I currently use ARC and I have quite a lot of blocks in my app, currently always referring to self instead of its weak reference. May that be the cause of these blocks retaining self and keeping it from being dealloced ? The question is, sho...
What is the way to quick-switch between tabs in Xcode 4
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That should be command + shift + ..., I think. At least on my machine.
– Chris Ladd
Feb 7 '12 at 21:54
1
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Get url parameters from a string in .NET
...ng "google.com/…" doesn't detect the parameter q
– Andrew Shepherd
Jun 30 '09 at 4:26
@Andrew I confirm. It's strang...
Mac OS X - EnvironmentError: mysql_config not found
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You did brew install mysql
You did export PATH=$PATH:/usr/local/mysql/bin
And finally, you did pip install MySQL-Python (or pip3 install mysqlclient if using python 3)
If you did all those steps in the same order, and you still got an error, read on to the end, if, however, you did not follow the...
How to get and set the current web page scroll position?
How can I get and set the current web page scroll position?
4 Answers
4
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How to split a string, but also keep the delimiters?
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You can use Lookahead and Lookbehind. Like this:
System.out.println(Arrays.toString("a;b;c;d".split("(?<=;)")));
System.out.println(Arrays.toString("a;b;c;d".split("(?=;)")));
System.out.println(Arrays.toString("a;b;c;d".split("((?<=;)|(?=;...
Append column to pandas dataframe
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@BenDundee Join and concat use a lot of the same code under the hood, so the "right" way probably only matters when you consider edge cases. For instance here if both DataFrames had a 'data' column the join would fail, whereas a concat would...
django unit tests without a db
... db? I want to test business logic which doesn't require the db to set up. And while it is fast to setup a db, I really don't need it in some situations.
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Why can't C++ be parsed with a LR(1) parser?
I was reading about parsers and parser generators and found this statement in wikipedia's LR parsing -page:
6 Answers
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