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Undo scaffolding in Rails
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First, if you have already run the migrations generated by the scaffold command, you have to perform a rollback first.
rake db:rollback
You can create scaffolding using:
rails generate scaffold MyFoo
(or similar), and you can destroy/undo it using
rails destroy scaffold M...
How do I change the background color of a plot made with ggplot2
By default, ggplot2 produces plots with a grey background. How do I change the color of the background of the plot?
3 Answ...
Why is it wrong to use std::auto_ptr with standard containers?
...n for extension. Lazer said what was not said before here. I guess he came by by chance.
– Sebastian Mach
Nov 18 '11 at 16:21
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Aspect Oriented Programming vs. Object-Oriented Programming
..."meta-programming". Everything that AOP does could also be done without it by just adding more code. AOP just saves you writing this code.
Wikipedia has one of the best examples for this meta-programming. Assume you have a graphical class with many "set...()" methods. After each set method, the data...
Manipulate a url string by adding GET parameters
I want to add GET parameters to URLs that may and may not contain GET parameters without repeating ? or & .
15 Answe...
MySQL - why not index every field?
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@Richard aka cyberkiwi: Indexes are not covered by ANSI - it's a miracle each vendor has used similar terminology. But even then, only SQL Server and MySQL use the terminology "clustered" and "non-clustered" index -- it means more in SQL Server than MySQL at that. There ...
How do Google+ +1 widgets break out of their iframe?
...unning within the context of your website and therefore is not constrained by the Origin Inheritance Rules for iframes. Therefore this JavaScript widget can set whatever DOM events it wants on the parent site even though it appears to be just a simple iframe.
Another thing, why is Google using an...
PSQLException: current transaction is aborted, commands ignored until end of transaction block
...ause you are using a broken transaction to do additional work. PostgreSQL by default stops you from doing this.
I'm using: PostgreSQL 9.1.6 on x86_64-redhat-linux-gnu, compiled by gcc (GCC) 4.7.2 20120921 (Red Hat 4.7.2-2), 64-bit".
My PostgreSQL driver is: postgresql-9.2-1000.jdbc4.jar
Using Java ...
Sass calculate percent minus px
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You can always use a fall back option by adding width: 22% at above all widths with calc
– Hengjie
Sep 3 '13 at 6:14
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Overriding fields or properties in subclasses
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Of the three solutions only Option 1 is polymorphic.
Fields by themselves cannot be overridden. Which is exactly why Option 2 returns the new keyword warning.
The solution to the warning is not to append the “new” keyword, but to implement Option 1.
If you need your field to ...