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Unioning two tables with different number of columns
...dd extra columns as null for the table having less columns like
Select Col1, Col2, Col3, Col4, Col5 from Table1
Union
Select Col1, Col2, Col3, Null as Col4, Null as Col5 from Table2
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improv...
Bash script error [: !=: unary operator expected
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189
Quotes!
if [ "$1" != -v ]; then
Otherwise, when $1 is completely empty, your test becomes:
...
Google Maps API v3: How do I dynamically change the marker icon?
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182
Call the marker.setIcon('newImage.png')... Look here for the docs.
Are you asking about the a...
What is the preferred syntax for initializing a dict: curly brace literals {} or the dict() function
...e keys are valid Python identifiers.
This works:
a = {'import': 'trade', 1: 7.8}
a = dict({'import': 'trade', 1: 7.8})
This won't work:
a = dict(import='trade', 1=7.8)
>> SyntaxError: invalid syntax ^
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Return index of greatest value in an array
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12 Answers
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Nginx url重写rewrite实例详解 - 更多技术 - 清泛网移动版 - 专注C/C++及内核技术
...rewrite在nginx中实现url重写，学习rewrite的具体用法，包括301重定向的内容等，希望对大家有所帮助。nginx rewrite 实现二级域名跳转
当访问http://www.jbyuan.com跳转到http://www.jbyuan.com/nvxingjiankang/
方法一：
这种方法浏览器地址会变www.j...
Retrieving the last record in each group - MySQL
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1021
MySQL 8.0 now supports windowing functions, like almost all popular SQL implementations. With...
Creating a zero-filled pandas data frame
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140
You can try this:
d = pd.DataFrame(0, index=np.arange(len(data)), columns=feature_list)
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How can I convert spaces to tabs in Vim or Linux?
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318
Using Vim to expand all leading spaces (wider than 'tabstop'), you were right to use retab but ...
Take the content of a list and append it to another list
...
You probably want
list2.extend(list1)
instead of
list2.append(list1)
Here's the difference:
>>> a = range(5)
>>> b = range(3)
>>> c = range(2)
>>> b.append(a)
>>> b
[0, 1, 2, [0, 1, 2, 3, 4]]
>>> c.ex...