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Adding :default => true to boolean in existing Rails column
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change_column is a method of ActiveRecord::Migration, so you can't call it like that in the console.
If you want to add a default value for this column, create a new migration:
rails g migration add_default_value_to_show_attribute
Then in the migration created:
# That's the more generic way t...
how to add script src inside a View when using Layout
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BTW, sections are essentially your contentplaceholders you were referring to. See the default MVC web project and how they place a heading on the page.
– Brad Christie
Jan 11 '13 at 18:57
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Updating MySQL primary key
I have a table user_interactions with 4 columns:
3 Answers
3
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How to test equality of Swift enums with associated values
...d values.
So if you're on Swift 4.1 or newer, the following will automatically synthesize the necessary methods such that XCTAssert(t1 == t2) works. The key is to add the Equatable protocol to your enum.
enum SimpleToken: Equatable {
case Name(String)
case Number(Int)
}
let t1 = SimpleToke...
Why does comparing strings using either '==' or 'is' sometimes produce a different result?
...l reasons: it is
inherently O(n) in the length of the
strings; it typically requires reads
from several regions of memory, which
take time; and the reads fills up the
processor cache, meaning there is less
cache available for other needs. With
interned strings, a simple object
identi...
Find full path of the Python interpreter?
...3 and it printed the correct executable. I also tried with no shebang and called the script with the python and python3 commands and it printed the correct executable.
– David Baucum
Oct 10 '19 at 13:18
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What is the best way to give a C# auto-property an initial value?
...ty).
Example of attributes that impact the IL are ThreadStaticAttribute, CallerMemberNameAttribute, ...
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Correct Bash and shell script variable capitalization
I run across many shell scripts with variables in all caps, and I've always thought that there is a severe misunderstanding with that. My understanding is that, by convention (and perhaps by necessity long ago), environment variables are in all-caps.
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How to install MySQLdb (Python data access library to MySQL) on Mac OS X?
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Update for those using Python3:
You can simply use conda install mysqlclient to install the libraries required to use MySQLdb as it currently exists. The following SO question was a helpful clue: Python 3 ImportError: No module named 'ConfigParser' . Installing mysqlclient will install...
How to implement an abstract class in ruby?
I know there is no concept of abstract class in ruby. But if at all it needs to be implemented, how to go about it? I tried something like...
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