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Unresolved reference issue in PyCharm
... by simply telling pycharm that you want to add the src folder as a source root, and then adding the sources root to your python path.
This way, you don't have to hard code things into your interpreter's settings:
Add src as a source content root:
...
SQL Server equivalent to MySQL enum data type?
Does SQL Server 2008 have a a data-type like MySQL's enum ?
5 Answers
5
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How to copy data from one table to another new table in MySQL?
I want to copy data from one table to another in MySQL.
11 Answers
11
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How big can a MySQL database get before performance starts to degrade
At what point does a MySQL database start to lose performance?
15 Answers
15
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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...doesn't have to sort the output, and GROUP BY by default does. However, in MySQL even a DISTINCT+ORDER BY might still be faster than a GROUP BY due to the extra hints for the optimizer as explained by SquareCog.
– rustyx
Jan 25 '15 at 15:03
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String concatenation in Ruby
...;< but that is not the usual way
With string interpolation
source = "#{ROOT_DIR}/#{project}/App.config"
with +
source = "#{ROOT_DIR}/" + project + "/App.config"
The second method seems to be more efficient in term of memory/speed from what I've seen (not measured though). All three methods ...
内存优化总结:ptmalloc、tcmalloc和jemalloc - 操作系统(内核) - 清泛网 - ...
...，tcmalloc性能上也有明显的优势，并且相对平稳。
github mysql优化
github使用tcmalloc后，mysql性能提升30%
Jemalloc
jemalloc是facebook推出的， 最早的时候是freebsd的libc malloc实现。 目前在firefox、facebook服务器各种组件中大量使用。
jemall...
NGinx Default public www location?
... have worked with Apache before, so I am aware that the default public web root is typically /var/www/ .
30 Answers
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MySQL order by before group by
...pand on my comments about using a subquery to accurate return this data.
MySQL does not force you to GROUP BY every column that you include in the SELECT list. As a result, if you only GROUP BY one column but return 10 columns in total, there is no guarantee that the other column values which bel...
How to create a trie in Python
...; _end = '_end_'
>>>
>>> def make_trie(*words):
... root = dict()
... for word in words:
... current_dict = root
... for letter in word:
... current_dict = current_dict.setdefault(letter, {})
... current_dict[_end] = _end
... return ...