大约有 41,000 项符合查询结果(耗时:0.0396秒) [XML]
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...
Which is the preferred way to concatenate a string in Python?
... to a string, then to a list:
a += b:
0.10780501365661621
a.append(b):
0.1123361587524414
OK, turns out that even when the resulting string is a million characters long, appending was still faster.
Now let's try with appending a thousand character long string a hundred thousand times:
a += b:
0...
How to use hex color values
...
How would you handle 123ABC? The compiler is burking at it not being a digit.
– Islam Q.
Mar 2 '16 at 6:28
1
...
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.)
share
|
improve this answer
|
...
How to pass an array into a SQL Server stored procedure
...tion for this problem. You should only create an string expression like ';123;434;365;' in-which 123, 434 and 365 are some employeeIDs. By calling the below procedure and passing this expression to it, you can fetch your desired records. Easily you can join the "another table" into this query. This...
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());
...
Flatten nested dictionaries, compressing keys
...stance(dd, dict) else { prefix : dd }
Test:
In [2]: flatten_dict({'abc':123, 'hgf':{'gh':432, 'yu':433}, 'gfd':902, 'xzxzxz':{"432":{'0b0b0b':231}, "43234":1321}}, '.')
Out[2]:
{'abc': 123,
'gfd': 902,
'hgf.gh': 432,
'hgf.yu': 433,
'xzxzxz.432.0b0b0b': 231,
'xzxzxz.43234': 1321}
...
App Inventor 2 列表代码块 · App Inventor 2 中文网
...异常、报错。
如果给定列表是一个二维列表,如 [["abc","123"],["xyz","456"]] ,则返回的列表项也是一个列表对象,如 ["abc","123"]。
求对象在列表中的位置
返回指定对象在列表中的位置,从 1 开始,如果不在列...
Difference between filter and filter_by in SQLAlchemy
...
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.
...
How to convert wstring into string?
... answered Aug 22 '13 at 7:57
dk123dk123
14k1616 gold badges6060 silver badges7171 bronze badges
...