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Best way to test if a row exists in a MySQL table
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edited Sep 4 '19 at 19:20
SovietFrontier
1,5441010 silver badges2727 bronze badges
answered Nov 4 '09 ...
What is the Difference Between read() and recv() , and Between send() and write()?
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130
The difference is that recv()/send() work only on socket descriptors and let you specify certain...
MySQL - Rows to Columns
...temvalue |
+--------+----------+-----------+
| 1 | A | 10 |
| 1 | B | 3 |
| 2 | A | 9 |
| 2 | C | 40 |
+--------+----------+-----------+
This will be our goal, the pretty pivot table:
select * from history_itemvalue_piv...
How to access pandas groupby dataframe by key
...group method:
In [21]: gb.get_group('foo')
Out[21]:
A B C
0 foo 1.624345 5
2 foo -0.528172 11
4 foo 0.865408 14
Note: This doesn't require creating an intermediary dictionary / copy of every subdataframe for every group, so will be much more memory-efficient that creating...
How do I get my Python program to sleep for 50 milliseconds?
How do I get my Python program to sleep for 50 milliseconds?
6 Answers
6
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Shuffle two list at once with same order
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– Jaroslav Klimčík
Apr 25 '14 at 10:15
4
(noob question) - what does the * mean?
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Join a list of strings in python and wrap each string in quotation marks
...ords = ['hello', 'world', 'you', 'look', 'nice']
>>> ', '.join('"{0}"'.format(w) for w in words)
'"hello", "world", "you", "look", "nice"'
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What's quicker and better to determine if an array key exists in PHP?
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10 Answers
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top命令使用详解 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...信息，同 uptime 命令的执行结果。其内容如下：
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