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How does Rails keep track of which migrations have run for a database?
According to Rails doc: http://guides.rubyonrails.org/migrations.html
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Are foreign keys really necessary in a database design?
... know, foreign keys (FK) are used to aid the programmer to manipulate data in the correct way. Suppose a programmer is actually doing this in the right manner already, then do we really need the concept of foreign keys?
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Escaping regex string
I want to use input from a user as a regex pattern for a search over some text. It works, but how I can handle cases where user puts characters that have meaning in regex?
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How to insert tab character when expandtab option is on in Vim
When I'm in insert mode and I have the expandtab option switched on, pressing Tab ↹ results in inserting the configured number of spaces.
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In Objective-C, what is the equivalent of Java's “instanceof” keyword?
...signable (cast-able) to a variable of another type (e.g. SpecifiedType ). In Java, I can write:
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How to copy a collection from one database to another in MongoDB
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At the moment there is no command in MongoDB that would do this. Please note the JIRA ticket with related feature request.
You could do something like:
db.<collection_name>.find().forEach(function(d){ db.getSiblingDB('<new_database>')['<colle...
Sending “User-agent” using Requests library in Python
I want to send a value for "User-agent" while requesting a webpage using Python Requests. I am not sure is if it is okay to send this as a part of the header, as in the code below:
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Groovy / grails how to determine a data type?
What is the best way to determine the data type in groovy?
5 Answers
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is guava-libraries available in maven repo?
I am looking to find guava-libraries in maven repository. It looks like guava is adding more features to google-collections library.
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Difference between final static and static final
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No difference at all. According to
8.3.1 - Classes - Field Modifiers of the Java Language Specification,
If two or more (distinct) field modifiers appear in a field declaration, it is customary, though not required, that they appear in the order co...