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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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Is the Javascript date object always one day off?

... Notice that Eastern Daylight Time is -4 hours and that the hours on the date you're getting back are 20. 20h + 4h = 24h which is midnight of 2011-09-24. The date was parsed in UTC (GMT) because you provided a date-only string without any time zone indicator. If you had ...
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Scatterplot with marginal histograms in ggplot2

...he sample below in ggplot2 ? In Matlab it is the scatterhist() function and there exist equivalents for R as well. However, I haven't seen it for ggplot2. ...
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When to use IComparable Vs. IComparer

...rer<T> is useful for sorting collections as the IComparer<T> stands outside of the comparison. share | improve this answer | follow | ...
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How to bring view in front of everything?

I have activity and a lot of widgets on it, some of them have animations and because of the animations some of the widgets are moving (translating) one over another. For example the text view is moving over some buttons . . . ...
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encryption/decryption with multiple keys

... GnuPG does multi-key encryption in standard. The following command will encrypt doc.txt using the public key for Alice and the public key for Bob. Alice can decrypt using her private key. Bob can also decrypt using his private key. gpg --encrypt --recipient al...
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How to do SELECT COUNT(*) GROUP BY and ORDER BY in Django?

..., add the annotation (this will add an extra field to the returned values) and finally, you order them by this value Refer to https://docs.djangoproject.com/en/dev/topics/db/aggregation/ for more insight Good to note: if using Count, the value passed to Count does not affect the aggregation, just th...
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Excel VBA App stops spontaneously with message “Code execution has been halted”

...expected solution for a bizarre problem. After pressing [Ctrl+Break] twice and continuing, I saved the file. After that, the problem no longer appeared when I closed and re-opened the file. – dbenham Oct 1 '12 at 16:59 ...
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Detecting if an NSString contains…?

... Actually you can just add space on the beginning and end of the string and " is " will match string begins with "is" – user4951 Nov 12 '12 at 7:41 ...
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CSS Font Border?

... a -webkit prefix. h1 { -webkit-text-stroke: 2px black; /* width and color */ font-family: sans; color: yellow; } <h1>Hello World</h1> Another possible trick would be to use four shadows, one pixel each on all directions, using property text-shadow: h1 { ...