大约有 47,000 项符合查询结果（耗时：0.0824秒） [XML]
Python (and Python C API): __new__ versus __init__
...vs immutable types.
__new__ accepts a type as the first argument, and (usually) returns a new instance of that type. Thus it is suitable for use with both mutable and immutable types.
__init__ accepts an instance as the first argument and modifies the attributes of that instance. This is inappropr...
How do I spool to a CSV formatted file using SQLPLUS?
...tion on IDs)
spool myfile.csv
select table_name, tablespace_name
from all_tables
where owner = 'SYS'
and tablespace_name is not null;
Output will be like:
TABLE_PRIVILEGE_MAP ,SYSTEM
SYSTEM_PRIVILEGE_MAP ,SYSTEM
...
After Installing Java JDK 7 For Mac OS X - mvn -version still shows java version 1.6.0_31
Oracle released Java JDK 7 on April 26 for Mac OS X. I followed the install instructions and when I do java -version in a terminal window I get:
...
How to serve static files in Flask
...ample below, I have moved my templates and static files into a sub-folder called web.
app = Flask(__name__,
static_url_path='',
static_folder='web/static',
template_folder='web/templates')
static_url_path='' removes any preceding path from the URL (i.e.
the d...
What is a mixin, and why are they useful?
...
Probably not an issue in this example, but you generally want to put the main base class as the last element within the parenthesis so to create the inheritance chain: Request==>Mixin==>...==>BaseRequest. See here: ianlewis.org/en/mixins-and-python
...
PowerShell script to return versions of .NET Framework on a machine?
...t). It also outputs both Client and Full on 4.0 (if you have them both installed):
Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -recurse |
Get-ItemProperty -name Version,Release -EA 0 |
Where { $_.PSChildName -match '^(?!S)\p{L}'} |
Select PSChildName, Version, Release
Based o...
How to list branches that contain a given commit?
...uery git to find out which branches contain a given commit? gitk will usually list the branches, unless there are too many, in which case it just says "many (38)" or something like that. I need to know the full list, or at least whether certain branches contain the commit.
...
Python division
...-100 and was having problems only to notice that even with no variables at all, this does not evaluate the way I would expect it to:
...
How to apply bindValue method in LIMIT clause?
...
@Ross I cannot specifically answer this- but I can point out that LIMIT and OFFSET are features that were glued on AFTER all this PHP/MYSQL/PDO madness hit the dev circuit... In fact, I believe it was Lerdorf himself who oversaw LIMIT implementatio...
Can you add new statements to Python's syntax?
... a hands-on approach here: I'm going to add an until statement to Python.
All the coding for this article was done against the cutting-edge Py3k branch in the Python Mercurial repository mirror.
The until statement
Some languages, like Ruby, have an until statement, which is the complement to whi...