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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.
share...
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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Error java.lang.OutOfMemoryError: GC overhead limit exceeded
...t'll be hard to tell which one is misbehaving. Separating the applications into distinct JVMs might be the easiest solution.
– Joachim Sauer
Mar 1 '12 at 11:48
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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 advantage of using abstract classes instead of traits?
...ure even traits can have constructor parameters
Abstract classes are fully interoperable with Java. You can call them from Java code without any wrappers. Traits are fully interoperable only if they do not contain any implementation code
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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...
The constant cannot be marked static
...tance to reference the const value).
I want to also add this important point: When you link against (reference) an assembly with a public const, that value is copied into your assembly. So if the const value in the referenced assembly changes, your assembly will still have the originally compiled-...
MySQL - Rows to Columns
...three-step process (with an optional fourth step):
select the columns of interest, i.e. y-values and x-values
extend the base table with extra columns -- one for each x-value
group and aggregate the extended table -- one group for each y-value
(optional) prettify the aggregated table
Let's apply...