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What is scope/named_scope in rails?
... scope :fresh, -> { where('age < ?', 25) }
scope :recent, -> { order(created_at: :desc) }
end
And you call
Zombie.rotting.fresh.recent.limit(3)
It translates to the below in SQL,
select "zombies.*" from "zombies" where "zombies"."rotting" = 't' and (age<20) order by create_at de...
What is the maximum length of data I can put in a BLOB column in MySQL?
...t be accurate, but according to this site: http://www.htmlite.com/mysql003.php.
BLOB A string with a maximum length of 65535 characters.
The MySQL manual says:
The maximum size of a BLOB or TEXT
object is determined by its type, but
the largest value you actually can
transmit betwe...
Reorder / reset auto increment primary key
...mary key column and re-create it. All the ids should then be reassigned in order.
However this is probably a bad idea in most situations. If you have other tables that have foreign keys to this table then it will definitely not work.
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How do I check if a type is a subtype OR the type of an object?
..., it's a bit awkward to read and write, and easy to mess up (reversing the order of potentialBase and potentialDescendant can be deadly).
– jrh
Dec 11 '17 at 13:40
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MPICH vs OpenMPI
...xtensive optimizations that make it the preferred implementation in nearly all cases.
Feature Support from the Latest MPI Standard
An orthogonal axis to hardware/platform support is coverage of the MPI standard. Here MPICH is usually far and away superior. MPICH has been the first implementation...
How to get share counts using graph API
I can get the share count of an URL using PHP SDK and using the deprecated rest API, but didn't find a way to get the share counts of an URL using graph API.
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How to sort List of objects by some property
...d idea to implement Comparable<T> if there's a single "natural" sort order... otherwise (if you happen to want to sort in a particular order, but might equally easily want a different one) it's better to implement Comparator<T>. This particular situation could go either way, to be honest...
Do DOM tree elements with ids become global variables?
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Save An Image To Application Documents Folder From UIView On IOS
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Why is using the rails default_scope often recommend against?
... of default_scope is when you want something to be sorted: default_scope { order(:name) }.
– user2985898
Aug 25 '16 at 9:33
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