大约有 40,000 项符合查询结果（耗时：0.0255秒） [XML]
Why was the switch statement designed to need a break?
...
2. Antipatterns: Doesn't provide "clean" tagged unions, one of the two fundamental data-representation idioms of assembly. (Knuth, vol 1, ch 2) Instead, "untagged unions," a non-idiomatic hack. This choice has hobbled the way people think of data for decades. And NUL-termi...
Is the “struct hack” technically undefined behavior?
...n the above trick for getting the right size, you might also need to put a union containing every simple type before the array, to ensure that the array itself begins with maximal alignment rather than in the middle of some other element's padding. Again, I don't believe any of this is necessary, bu...
How do I modify fields inside the new PostgreSQL JSON datatype?
With postgresql 9.3 I can SELECT specific fields of a JSON data type, but how do you modify them using UPDATE? I can't find any examples of this in the postgresql documentation, or anywhere online. I have tried the obvious:
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SQL RANK() versus ROW_NUMBER()
...he first 3 rows are tied when ordered by ID)
WITH T(StyleID, ID)
AS (SELECT 1,1 UNION ALL
SELECT 1,1 UNION ALL
SELECT 1,1 UNION ALL
SELECT 1,2)
SELECT *,
RANK() OVER(PARTITION BY StyleID ORDER BY ID) AS 'RANK',
ROW_NUMBER() OVER(PARTITION BY Style...
What do the following phrases mean in C++: zero-, default- and value-initialization?
...object is set to the value of 0 (zero) converted to T;
— if T is a non-union class type, each nonstatic data member and each base-class subobject is zero-initialized;
— if T is a union type, the object’s first named data member is zero-initialized;
— if T is an array type, each element...
how to exclude null values in array_agg like in string_agg using postgres?
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SQL Fiddle
select
id,
(select array_agg(a) from unnest(canonical_users) a where a is not null) canonical_users,
(select array_agg(a) from unnest(non_canonical_users) a where a is not null) non_canonical_users
from (
SELE...
What is the purpose of std::make_pair vs the constructor of std::pair?
... Also note that make_pair works with unnamed types, including structs, unions, lambdas, and other doodads.
– Mooing Duck
Feb 6 '15 at 22:29
add a comment
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Preserving order with LINQ
...p a source element by index to a result element
AsEnumerable
Cast
Concat
Select
ToArray
ToList
Preserves Order. Elements are filtered or added, but not re-ordered.
Distinct
Except
Intersect
OfType
Prepend (new in .net 4.7.1)
Skip
SkipWhile
Take
TakeWhile
Where
Zip (new in .net 4)
Destroys O...
google mock分享（全网最全最好的gmock文档，没有之一） - C/C++ - 清泛网 ...
...IANTFIELD_H_
#include <boost/cstdint.hpp>
namespace seamless {
union VariantField
{
const char * strVal;
int32_t intVal;
};
} // namespace mlr_isearch_api
#endif // VARIANTFIELD_H_
IParameterInterface.h 提供一个接口，用于得到Query中的各个Segment的...
Variable declaration placement in C
...ly if the curlies are part of a block (not if they are part of a struct or union declaration or a braced initializer.)
– Jens
Jun 18 '13 at 19:39
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