大约有 40,000 项符合查询结果（耗时：0.0431秒） [XML]
How does BLAS get such extreme performance?
...e optimization. This boost significantly exceeds the second boost from parallelism and other hardware optimizations.
By the way, most (or even all) of the high performance BLAS implementations are NOT implemented in Fortran. ATLAS is implemented in C. GotoBLAS/OpenBLAS is implemented in C and i...
SQL Joins Vs SQL Subqueries (Performance)?
...explicit JOIN. In my experience IN is a very slow operator, since SQL normally evaluates it as a series of WHERE clauses separated by "OR" (WHERE x=Y OR x=Z OR...).
As with ALL THINGS SQL though, your mileage may vary. The speed will depend a lot on indexes (do you have indexes on both ID column...
Class.forName() vs ClassLoader.loadClass() - which to use for dynamic loading? [duplicate]
When dynamically loading a class, when is it appropriate to use
6 Answers
6
...
SQLAlchemy: Creating vs. Reusing a Session
Just a quick question: SQLAlchemy talks about calling sessionmaker() once but calling the resulting Session() class each time you need to talk to your DB. For me that means the second I would do my first session.add(x) or something similar, I would first do
...
How do I convert datetime to ISO 8601 in PHP
... than ISO8601 (the colon is missing in the TZ, ISO8601 expects times to be all with OR all without the colon, not a mixture) - date('c') does produces a strict ISO 8601 valid date - This could cause hard to trace bugs if code expects a strict ISO 8601 datetime format. Ref: en.wikipedia.org/wiki/ISO_...
Choosing a Windows automation scripting language. AutoIt vs Autohotkey [closed]
...
Nonetheless AHK does have a intrinsically more arcane syntax, which is not as user- or beginner friendly as AutoIt. AutoIt is more developer friendly for large projects and supports a more modern, intuitive syntax. AHK really shines in what it's named for. Hotke...
htmlentities() vs. htmlspecialchars()
... for htmlentities:
This function is identical to htmlspecialchars() in all ways, except with htmlentities(), all characters which have HTML character entity equivalents are translated into these entities.
From the PHP documentation for htmlspecialchars:
Certain characters have special sig...
Integer.toString(int i) vs String.valueOf(int i)
...
String.valueOf(int) just calls Integer.toString(i) directly. So best to call Integer.toString(int).
– djchapm
May 21 '19 at 16:21
...
Object.getOwnPropertyNames vs Object.keys
...
There is a little difference. Object.getOwnPropertyNames(a) returns all own properties of the object a. Object.keys(a) returns all enumerable own properties. It means that if you define your object properties without making some of them enumerable: false these two methods will give you the sa...
NameValueCollection vs Dictionary [duplicate]
...
They aren't semantically identical. The NameValueCollection can have duplicate keys while the Dictionary cannot.
Personally if you don't have duplicate keys, then I would stick with the Dictionary. It's more modern, uses IEnumerable<> wh...