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How do you write a migration to rename an ActiveRecord model and its table in Rails?
I'm terrible at naming and realize that there are a better set of names for my models in my Rails app. Is there any way to use a migration to rename a model and its corresponding table?
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CSS media queries: max-width OR max-height
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Use a comma to specify two (or more) different rules:
@media screen and (max-width: 995px) , screen and (max-height: 700px) {
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}
From https://developer.mozilla.org/en/CSS/Media_queries/
...In addition, you can combine multiple media queries in a comma-separated list; if any of the ...
MySQL: Quick breakdown of the types of joins [duplicate]
...ma separated example you gave of
SELECT * FROM a, b WHERE b.id = a.beeId AND ...
is selecting every record from tables a and b with the commas separating the tables, this can be used also in columns like
SELECT a.beeName,b.* FROM a, b WHERE b.id = a.beeId AND ...
It is then getting the instru...
Search text in fields in every table of a MySQL database
...u can peek into the information_schema schema. It has a list of all tables and all fields that are in a table. You can then run queries using the information that you have gotten from this table.
The tables involved are SCHEMATA, TABLES and COLUMNS. There are foreign keys such that you can build u...
Is it possible to get the iOS 5.1 SDK for Xcode 4.2 on Snow Leopard?
...d. I have Xcode 4.2 for iOS development. This morning I upgraded my iPhone and iPad to iOS 5.1.
15 Answers
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In C/C++ what's the simplest way to reverse the order of bits in a byte?
...e, I'm curious as to what is the "simplest" for a developer to implement. And by reversing I mean:
35 Answers
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Big-O for Eight Year Olds? [duplicate]
I'm asking more about what this means to my code. I understand the concepts mathematically, I just have a hard time wrapping my head around what they mean conceptually. For example, if one were to perform an O(1) operation on a data structure, I understand that the number of operations it has to p...
Why all the Active Record hate? [closed]
As I learn more and more about OOP, and start to implement various design patterns, I keep coming back to cases where people are hating on Active Record .
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Python syntax for “if a or b or c but not all of them”
I have a python script that can receive either zero or three command line arguments. (Either it runs on default behavior or needs all three values specified.)
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What is an unsigned char?
...ich gives you at least the 0 to 255 range.
"At least", because the C++ standard only gives the minimum range of values that each numeric type is required to cover. sizeof (char) is required to be 1 (i.e. one byte), but a byte could in theory be for example 32 bits. sizeof would still be report its...