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Rails “validates_uniqueness_of” Case Sensitivity
... 3rd Edition:
...despite its name, validates_uniqueness_of doesn’t really guarantee that column values will be unique. All it can do is verify that no column has the same value as that in the record being validated at the time the validation is performed. It’s possible for two records to be ...
What part of Hindley-Milner do you not understand?
...re are multiple expressions in [above], then consider them anded together; all of the [above] must be true in order to guarantee the [below].
: means has type
∈ means is in. (Likewise ∉ means "is not in".)
Γ is usually used to refer to an environment or context; in this case it can be thought o...
How to JSON serialize sets?
...s.
As shown in the json module docs, this conversion can be done automatically by a JSONEncoder and JSONDecoder, but then you would be giving up some other structure you might need (if you convert sets to a list, then you lose the ability to recover regular lists; if you convert sets to a dictionar...
rgdal package installation
...liam Kyngesburye at http://www.kyngchaos.com/ may be used for
source installs on OSX.
As you seem to be under Linux, you always build package from source, so you will have to install the corresponding libraries on your system. If you are under Mint, Ubuntu or another Debian derivative, you can d...
How to convert a Collection to List?
...
Something like this should work, calling the ArrayList constructor that takes a Collection:
List theList = new ArrayList(coll);
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improve this answer...
Are table names in MySQL case sensitive?
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This totally burned me as my code was working great on my local windows environment, but throwing exceptions when moved into production on linux!! Thanks!
– portforwardpodcast
Feb 14 '13 at 21:1...
How to use cURL to get jSON data and decode the data?
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I've updated the question with the small difficulty I am having working with the PHP array that is returned by jSON. Please read the bottom part of it if you can.
– Maaz
May 22 '13 at 21:30
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decorators in the python standard lib (@deprecated specifically)
...r('always', DeprecationWarning) # turn off filter
warnings.warn("Call to deprecated function {}.".format(func.__name__),
category=DeprecationWarning,
stacklevel=2)
warnings.simplefilter('default', DeprecationWarning) # reset filter
...
Create a nonclustered non-unique index within the CREATE TABLE statement with SQL Server
...ne index create option:
CREATE TABLE MyTable(
a int NOT NULL
,b smallint NOT NULL
,c smallint NOT NULL
,d smallint NOT NULL
,e smallint NOT NULL
-- This creates a primary key
,CONSTRAINT PK_MyTable PRIMARY KEY CLUSTERED (a)
-- This creates a unique nonclustered ind...
How to set cursor position in EditText?
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