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Using Rails serialize to save hash to database
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add_column :users, :multi_wrong, :text
end
Then Rails will properly convert it into YAML for you (and perform proper serialization). Strings fields are limited in size and will only hold especially-small values.
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How do I check if a given string is a legal/valid file name under Windows?
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2nd piece of code doesn't compile. "Cannot convert from char[] to string
– Paul Hunt
Apr 25 '14 at 12:03
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How to initialize HashSet values by construction?
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Again, this is not time efficient since you are constructing an array, converting to a list and using that list to create a set.
When initializing static final sets I usually write it like this:
public static final String[] SET_VALUES = new String[] { "a", "b" };
public static final Set<Str...
HTML select form with option to enter custom value
...ext, to a GET of the same page as a query string. Does anyone know how to convert the action to a POST, so I can grab the value in a php file and do something with it there?
– Han
Sep 29 '19 at 8:17
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In C#, how can I create a TextReader object from a string (without writing to disk)
...es a TextReader object, and all I have is a string. What's the best way to convert a string into a TextReader object on the fly?
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What is the difference between pluck and collect in Rails?
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Yes. According to Rails guides, pluck directly converts a database result into an array, without constructing ActiveRecord objects. This means better performance for a large or often-running query.
In addition to @apneadiving's answer, pluck can take both single and mult...
PostgreSQL: Can you create an index in the CREATE TABLE definition?
...TE TABLE syntax. PostgreSQL does however create an index for unique constraints and primary keys by default, as described in this note:
PostgreSQL automatically creates an index for each unique constraint and primary key constraint to enforce uniqueness.
Other than that, if you want a non-uniq...
How to get the list of all printers in computer
I need to get the list of all printers that connect to computer?
6 Answers
6
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Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_
...red a very weird effect: Changing the loop variable from unsigned to uint64_t made the performance drop by 50% on my PC.
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iterating over each character of a String in ruby 1.8.6 (each_char)
... in an ASCII string:
"ABCDEFG".each_byte do |i|
puts i.chr # Fixnum#chr converts any number to the ASCII char it represents
end
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