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Check if a table exists in Rails
...came explicit regarding tables/views, collectively data sources.
# Tables and views
ActiveRecord::Base.connection.data_sources
ActiveRecord::Base.connection.data_source_exists? 'kittens'
# Tables
ActiveRecord::Base.connection.tables
ActiveRecord::Base.connection.table_exists? 'kittens'
# Views
Ac...
NSString: isEqual vs. isEqualToString
What is the difference between isEqual: and isEqualToString: ?
5 Answers
5
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How do I install package.json dependencies in the current directory using npm
...ent dir of your app if you want, because node's 'require' mechanism understands this. However, if you want to update your app's dependencies with install/update, npm will not see the relocated 'node_modules' and will instead create a new dir, again relative to package.json.
To prevent this, just cr...
how to fire event on file select
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and what happens when you submit the form asynchronously, don't navigate away from the page, then attempt to upload the same file again? This code will only execute once, the second time, selecting the same file will not exe...
How can you hide database output in Rails console?
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Thanks. And to turn it back on, ActiveRecord::Base.logger.level = 0.
– thebenedict
Nov 19 '13 at 8:34
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How does the Java 'for each' loop work?
...or any object that implements the Iterable interface.
Also, if the right-hand side of the for (:) idiom is an array rather than an Iterable object, the internal code uses an int index counter and checks against array.length instead. See the Java Language Specification.
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How to replace captured groups only?
I have HTML code before and after the string:
5 Answers
5
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What is the difference between 'log' and 'symlog'?
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I finally found some time to do some experiments in order to understand the difference between them. Here's what I discovered:
log only allows positive values, and lets you choose how to handle negative ones (mask or clip).
symlog means symmetrical log, and allows positive and negative valu...
Python, compute list difference
...vation is important Roman Bodnarchuk may have a better approach. For speed and pure set-like behavior this one seems better.
– Bryan P
Feb 13 '15 at 23:01
8
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What is __main__.py?
...hat is the __main__.py file for, what sort of code should I put into it, and when should I have one?
5 Answers
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