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Is there any difference between GROUP BY and DISTINCT
...ukas Eder
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Understanding :source option of has_one/has_many through of Rails
...'ve chosen to namespace the Dog::Breed, because we want to access Dog.find(123).breeds as a nice and convenient association.
Now, if we now want to create a has_many :dog_breeds, :through => :dogs association on Pet, we suddenly have a problem. Rails won't be able to find a :dog_breeds associati...
Convert Rows to columns using 'Pivot' in SQL Server
..., 212),
(105, 2, 78),
(109, 2, 97),
(105, 3, 60),
(102, 3, 123),
(101, 3, 220),
(109, 3, 87);
If your values are known, then you will hard-code the query:
select *
from
(
select store, week, xCount
from yt
) src
pivot
(
sum(xcount)
for week in ([1], [2], [3])
) pi...
Cast a Double Variable to Decimal
...hould use the M when declaring a new literal decimal value:
decimal dec = 123.45M;
(Without the M, 123.45 is treated as a double and will not compile.)
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TypeScript function overloading
... ...;
var n: number = foo1.bar('baz'); // OK
var s: string = foo1.bar(123); // OK
var a: number[] = foo1.bar([1,2,3]); // ERROR
The actual definition of the function must be singular and perform the appropriate dispatching internally on its arguments.
For example, using a class (which ...
how to change default python version?
...in 8 Apr 28 15:51 pydoc3@ -> pydoc3.2
-rwxrwxr-x 1 root admin 123 Feb 20 11:14 pydoc3.2*
-rwxrwxr-x 2 root admin 25624 Feb 20 11:14 python3*
lrwxr-xr-x 1 root admin 12 Apr 28 15:51 python3-32@ -> python3.2-32
lrwxr-xr-x 1 root admin 16 Apr 28 15:51 python3-config@ -&gt...
Fastest way to check if a string is JSON in PHP?
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$phone = '021234567'; var_dump(isJson($phone)); return true no! it should return false.
– vee
Jan 2 '14 at 17:12
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What is a method group in C#?
...) overload which takes a string parameter:
Func<string,string> fn = 123.ToString;
Console.WriteLine(fn("00000000"));
This example picks the ToString() overload which takes no parameters:
Func<string> fn = 123.ToString;
Console.WriteLine(fn());
...
jQuery Data vs Attr?
...you'll need to use .attr():
HTML:
<a id="foo" href="#" data-color="ABC123"></a>
<a id="bar" href="#" data-color="654321"></a>
JS:
$('#foo').data('color').length; //6
$('#bar').data('color').length; //undefined, length isn't a property of numbers
$('#foo').attr('data-col...
Difference between filter and filter_by in SQLAlchemy
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Be careful when using .filter. a query like id=12345, query(users).filter(id == id) will not filter on users.id. Instead, it will evaluate id == id as True and return all users. You need to use .filter(users.id == id) (as demoed above). I made this mistake earlier today.
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