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How do I use a Boolean in Python?
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Actually Python didn't have a boolean type for a long time (as in old C), and some programmers still use integers instead of booleans.
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What is the difference between Non-Repeatable Read and Phantom Read?
What is the difference between non-repeatable read and phantom read?
9 Answers
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SQL Server Text type vs. varchar data type [closed]
I have variable length character data and want to store in SQL Server (2005) database. I want to learn some best practices about how to choose TEXT SQL type or choose VARCHAR SQL type, pros and cons in performance/footprint/function.
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How to install a gem or update RubyGems if it fails with a permissions error
... using gem install mygem or update RubyGems using gem update --system , and it fails with this error:
27 Answers
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Facebook database design?
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Keep a friend table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
EmailAddress
Password
Ge...
What is the “right” way to iterate through an array in Ruby?
...arts, is pretty good on this count. There's no difference between an array and a hash (maybe I'm naive, but this seems obviously right to me), and to iterate through either you just do
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Should I use pt or px?
What is the difference between pt and px in CSS? Which one should I use and why?
5 Answers
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StringIO in Python3
I am using Python 3.2.1 and I can't import the StringIO module. I use
io.StringIO and it works, but I can't use it with numpy 's genfromtxt like this:
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How to avoid isset() and empty()
I have several older applications that throw a lot of "xyz is undefined" and "undefined offset" messages when running on the E_NOTICE error level, because the existence of variables is not explicitly checked using isset() and consorts.
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How to dynamically compose an OR query filter in Django?
...eries there is also the option to use built in Q() object's constants Q.OR and Q.AND together with the add() method like so:
list = [1, 2, 3]
# it gets a bit more complicated if we want to dynamically build
# OR queries with dynamic/unknown db field keys, let's say with a list
# of db fields that c...