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Iterate through every file in one directory
...lways include . and .. (the current and parent directories). You will generally not want to work on them, so you can use Dir::each_child or Dir::children (as suggested by ma11hew28) or do something like this:
Dir.foreach('/path/to/dir') do |filename|
next if filename == '.' or filename == '..'
...
How to delete migration files in Rails 3
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I usually:
Perform a rake db:migrate VERSION=XXX on all environments, to the version before the one I want to delete.
Delete the migration file manually.
If there are pending migrations (i.e., the migration I removed was not the...
Assigning a variable NaN in python without numpy
...aking) be said to be equal to one another -- see What is the rationale for all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation...
Why would you use String.Equals over ==? [duplicate]
I recently was introduced to a large codebase and noticed all string comparisons are done using String.Equals() instead of ==
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Error handling principles for Node.js + Express.js applications?
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Error handling in Node.js is generally of the format A). Most callbacks return an error object as the first argument or null.
Express.js uses middleware and the middleware syntax uses B) and E) (mentioned below).
C) is bad practice if you ask me.
app.get('...
jQuery: how to change title of document during .ready()?
...ards is right. It's just a method to let Google read contents that are normally generated with AJAX, via HTML snapshots and some server side modifications.
– Sk8erPeter
Jul 23 '12 at 12:52
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Eclipse/Java code completion not working
...o previously suffering from Eclipse thinking my project was in 1.5 despite all options saying otherwise, so it must have been corrupted during this issue.
– Philip Guin
Jun 30 '13 at 6:51
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'IF' in 'SELECT' statement - choose output value based on column values
...tp://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html.
Additionally, you could handle when the condition is null. In the case of a null amount:
SELECT id,
IF(type = 'P', IFNULL(amount,0), IFNULL(amount,0) * -1) as amount
FROM report
The part IFNULL(amount,0) means when amount ...
iPhone App Minus App Store?
... member of the developer program. You can then use the adhoc system to install your application onto up to 100 devices. The developer program has the details but it involves adding UUIDs for each of the devices to your application package. UUIDs can be easiest retrieved using Ad Hoc Helper available...
LISTAGG in Oracle to return distinct values
...ve will work in most cases - list should be sorted , you may have to trim all trailing and leading space depending on your data.
If you have a alot of items in a group > 20 or big string sizes you might run into oracle string size limit 'result of string concatenation is too long'.
From oracl...