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How do I make a column unique and index it in a Ruby on Rails migration?
...1 for suggesting continuing to use the validates_uniqueness_of. The error handling is much cleaner using this method for the cost of a single indexed query I would suggest he does both
– Steve Weet
Sep 19 '09 at 22:08
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Remove columns from dataframe where ALL values are NA
I'm having trouble with a data frame and couldn't really resolve that issue myself:
The dataframe has arbitrary properties as columns and each row represents one data set .
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Error 1022 - Can't write; duplicate key in table
I'm getting a 1022 error regarding duplicate keys on create table command. Having looked at the query, I can't understand where the duplication is taking place. Can anyone else see it?
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SVN change username
...und a lot of examples on how to change the username for specific revisions and so on.
11 Answers
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is node.js' console.log asynchronous?
...mat.apply(this, arguments) + '\n');
};
So it simply does some formatting and writes to process.stdout, nothing asynchronous so far.
process.stdout is a getter defined on startup which is lazily initialized, I've added some comments to explain things:
.... code here...
process.__defineGetter__('s...
Differences between git pull origin master & git pull origin/master
What is the difference between git pull origin master and git pull origin/master ?
3 Answers
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What is the difference between POST and GET? [duplicate]
I've only recently been getting involved with PHP/AJAX/jQuery and it seems to me that an important part of these technologies is that of POST and GET .
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How to take emulator screenshots using Eclipse?
I need to take screenshots of an android application running on an emulator in Eclipse Galileo.
6 Answers
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The bare minimum needed to write a MSMQ sample application
I have been researching for over an hour and finding great samples of how to use MSMQ in C# and even one full chapter of a book about Message Queue...But for a quick test all I need is to cover is this scenario, not even in a perfect way, just for a quick demo:
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Should commit messages be written in present or past tense? [closed]
So which is it that you think is better and more intuitive?
12 Answers
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