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Rails DB Migration - How To Drop a Table?
...tp://api.rubyonrails.org/classes/ActiveRecord/Migration.html
More specifically, you can see how to drop a table using the following approach:
drop_table :table_name
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Graphviz: How to go from .dot to a graph?
...neato and twopi. If graphiz isn't in your path, figure out where it is installed and run it from there.
You can change the output format by varying the value after -T and choosing an appropriate filename extension after -o.
If you're using windows, check out the installed tool called GVEdit, it ma...
How is “=default” different from “{}” for default constructor and destructor?
I originally posted this as a question only about destructors, but now I'm adding consideration of the default constructor. Here's the original question:
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Tainted canvases may not be exported
... likely on your local drive!).
While testing try these workarounds:
Put all page related files (.html, .jpg, .js, .css, etc) on your desktop (not in sub-folders).
Post your images to a site that supports cross-domain sharing (like dropbox.com). Be sure you put your images in dropbox's public fol...
Custom fonts in iOS 7
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First of all I'm assuming that SpriteKit doesn't make any difference.
You need your font in .otf or .ttf copied to your project. For example in Supporting Files.
You need to edit .plist file. Add "Fonts provided by application" key ...
How are parameters sent in an HTTP POST request?
...nt in the request body, in the format that the content type specifies.
Usually the content type is application/x-www-form-urlencoded, so the request body uses the same format as the query string:
parameter=value&also=another
When you use a file upload in the form, you use the multipart/form-...
Combine multiple Collections into a single logical Collection?
...llections (e.g. 3 ArrayLists) as members of a class. Now, I want to expose all the elements to other classes so they can simply iterate over all elements (ideally, read only).
I'm using guava collections and I wonder how I could use guava iterables/iterators to generate a logical view on the interna...
Nullable Foreign Key bad practice?
... read.
Only if you know better than Chris Date "what first normal form really means". If x and y are both nullable, and indeed in some row x and y are both null, then WHERE x=y does not yield true. This proves beyond reasonable doubt that null is not a value (because any real value is always equ...
Including all the jars in a directory within the Java classpath
Is there a way to include all the jar files within a directory in the classpath?
25 Answers
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NoSQL - MongoDB vs CouchDB [closed]
...~2.5Gb
Text search integrated
GridFS to store big data + metadata (not actually an FS)
Data center aware
Best used: If you need dynamic queries. If you prefer to define indexes, not map/reduce functions. If you need good performance on a big DB. If you wanted CouchDB, but your data changes too muc...