大约有 48,000 项符合查询结果（耗时：0.0635秒） [XML]
How can I create a unique constraint on my column (SQL Server 2008 R2)?
... PK__Customer__3213E83FCC4A1DFA (n/a) (n/a) (n/a) (n/a) id
---- now adding the unique constraint
ALTER TABLE Customer ADD CONSTRAINT U_Name UNIQUE(Name)
-- Commands completed successfully.
sp_help Customer
---> index
---index_name index_description index_keys
---PK__Customer__3...
Why switch is faster than if
...ic byte-code offset. Thus, when you give the statement an offset of 3, it knows to jump ahead 3 to find the correct branch.
Lookup switch uses a binary search to find the correct code branch. This runs in O(log n) time, which is still good, but not the best.
For more information on this, see here:...
Difference between Document-based and Key/Value-based databases?
I know there are three different, popular types of non-sql databases.
2 Answers
2
...
Determine if a sequence contains all elements of another sequence using Linq [duplicate]
...nimum iteration even for methods with lambda expressions, such as OrderBy. Now, what you do inside those lambda expressions could be highly inefficient, but that is on you :-) I like the readability of yours too; I am considering adding your extension method with the Except implementation to get the...
Sort points in clockwise order?
...ious oversight that it was missing. The if statements could be reorganized now because some checks are redundant. For example, if the first condition in the first if statement is false, then the first condition of the second if must be true. I decided, however, to leave the code as it is for the sak...
Is there a Java equivalent to C#'s 'yield' keyword?
I know there is no direct equivalent in Java itself, but perhaps a third party?
6 Answers
...
PhpStorm wrap/surround selection?
...
I know this is a little late answer, but I hope anyone who looks this question get helped.
In PhpStorm, almost everything can be configured but a little tricky and takes some learning curve.
It's very common behaviour that sele...
Rails: Default sort order for a rails model?
...atenating them with periods between them, so with the above scopes you can now use Book.published.confirmed.
With this method, the query is not actually executed until actual results are needed (lazy evaluation), so 7 scopes could be chained together but only resulting in 1 actual database query,...
How do you use vim's quickfix feature?
...vimrc file:
map <C-j> :cn<CR>
map <C-k> :cp<CR>
Now you can navigate through the errors using ctrl-j and ctrl-k, which mimics the standard down and up motion commands j and k.
share
|
...
Dynamically adding a form to a Django formset with Ajax
... the formset
3) User clicks the back button in the browser
4) Formset is now reduced to the original form, all dynamically added forms are not there
This is not a defect with Paolo's script at all; but a fact of life with dom manipulation and browser's cache.
I suppose one could store the values...