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Unioning two tables with different number of columns
... I realized that this solution also works without having to list all the columns. So instead of Select Col1, Col2, Col3, Null as Col4, Null as Col5 from Table2, one can also do, Select *, Null as Col4, Null as Col5 from Table2.
– Pratik Patel
Sep 20 '...
C++使用OLE/COM高速读写EXCEL的源码 - C/C++ - 清泛网 - 专注C/C++及内核技术
...m/xianyunhe/archive/2011/09/25/2190485.html
http://blog.sina.com.cn/s/blog_6e51df7f01015cci.html
感谢原作者的无私奉献。
通过VC实现对Excel表格的操作的方法有多种，如：通过ODBC数据库实现，通过解析Excel表格文件，通过OLE/COM的实现。本文主要研...
C# binary literals
... @Dai that’s no different than hex literals. In other words, all constants are big endian, but stored little endian on Intel/AMD and most ARMs. 0xDEADBEEF will be stored as 0xEF 0xBE 0xAD 0xDE
– Cole Johnson
Sep 2 '19 at 18:28
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Wait for a void async method
...
await Task.Run(() => An_async_void_method_I_can_not_modify_now())
– themefield
Mar 12 '19 at 21:46
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Concurrent.futures vs Multiprocessing in Python 3
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I wouldn't call concurrent.futures more "advanced" - it's a simpler interface that works very much the same regardless of whether you use multiple threads or multiple processes as the underlying parallelization gimmick.
So, like virtuall...
What are the differences between the threading and multiprocessing modules?
...nd the multiprocessing modules in Python to run certain operations in parallel and speed up my code.
6 Answers
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Numpy: find first index of value fast
...ments it. If you use anaconda python distribution it should already be installed.
The code will be compiled so it will be fast.
@jit(nopython=True)
def find_first(item, vec):
"""return the index of the first occurence of item in vec"""
for i in xrange(len(vec)):
if item == vec[i]:
...
Django Admin - Disable the 'Add' action for a specific model
...also register MyAdmin like: admin.site.register(MyModel, MyModelAdmin) Add all into the admin.py of the models`s app folder.
– djangonaut
Apr 23 '18 at 9:16
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Using OR in SQLAlchemy
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From the tutorial:
from sqlalchemy import or_
filter(or_(User.name == 'ed', User.name == 'wendy'))
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Multiple columns index when using the declarative ORM extension of sqlalchemy
...e just Column objects, index=True flag works normally:
class A(Base):
__tablename__ = 'table_A'
id = Column(Integer, primary_key=True)
a = Column(String(32), index=True)
b = Column(String(32), index=True)
if you'd like a composite index, again Table is present here as usual you ju...