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PostgreSQL create table if not exists
...E
CREATE TABLE myschema.mytable (i integer);
END IF;
END
$func$;
Call:
SELECT create_mytable(); -- call as many times as you want.
Notes:
The columns schemaname and tablename in pg_tables are case-sensitive. If you double-quote identifiers in the CREATE TABLE statement, you need...
ViewModel Best Practices
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I create what I call a "ViewModel" for each view. I put them in a folder called ViewModels in my MVC Web project. I name them after the controller and action (or view) they represent. So if I need to pass data to the SignUp view on the Membe...
“query function not defined for Select2 undefined error”
...dy been initialized by the .select2({}) method. A better solution would be calling the destroy method first. Ex: $("#mySelectControl").select2("destroy").select2({});
– Dmitry S.
Sep 4 '14 at 18:41
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In a django model custom save() method, how should you identify a new object?
...ir warning that it seems to always equal False if you're checking it after calling super(TheModel, self).save(*args, **kwargs): github.com/django/django/blob/stable/1.10.x/django/db/models/…
– agilgur5
Jun 26 '16 at 5:52
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Sort a list from another list IDs
... thats why I upvoted too, does rely on knowing the document ID property is called Id. Its not specified in the question.
– Jodrell
Mar 7 '13 at 16:13
3
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Update MongoDB field using value of another field
...e code for "MongoDB 3.2 or newer". Since forEach is async nothing will typically get written in the last bulkWrite.
– Viktor Hedefalk
Oct 4 '19 at 8:35
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Equivalent of .try() for a hash to avoid “undefined method” errors on nil? [duplicate]
...lets you to dig in the hash deeper than you could with using direct .try() calls, if you want the code still look nice:
class Hash
def get_deep(*fields)
fields.inject(self) {|acc,e| acc[e] if acc}
end
end
You should be careful with various objects (especially params), because Strings and ...
Find object in list that has attribute equal to some value (that meets any condition)
...## [1, 2, 3, 4, 5, 5, 6] Will Return: ###
# 5
# 5
# Traceback (most recent call last):
# File "C:\Users\mousavin\workspace\Scripts\test.py", line 22, in <module>
# print(next(my_filter_iter).value)
# StopIteration
# You can do that None stuff or whatever at this point, if you don't lik...
Referring to the null object in Python
... if not value:
value = init_value()
In the above, did you mean to call init_value() when the value is set specifically to None, or did you mean that a value set to 0, or the empty string, or an empty list should also trigger the initialization? Like I said, be mindful. As it's often the cas...
How do I implement an Objective-C singleton that is compatible with ARC?
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What about if somebody calls [[MyClass alloc] init]? That would create a new object. How can we avoid this (other than declaring static MyClass *sharedInstance = nil outside the method).
– Ricardo Sanchez-Saez
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