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Most efficient T-SQL way to pad a varchar on the left to a certain length?
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edited Mar 28 '12 at 13:10
answered Sep 23 '08 at 15:50
A...
What is “thread local storage” in Python, and why do I need it?
...riable: I think he means values have no scope
– user1071847
Jul 1 at 15:47
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When to use MongoDB or other document oriented database systems? [closed]
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Python using enumerate inside list comprehension
...$ python -mtimeit -s"mylist = ['a','b','c','d']" "list(enumerate(mylist))"
1000000 loops, best of 3: 1.61 usec per loop
~$ python -mtimeit -s"mylist = ['a','b','c','d']" "[(i, j) for i, j in enumerate(mylist)]"
1000000 loops, best of 3: 0.978 usec per loop
~$ python -mtimeit -s"mylist = ['a','b','c'...
postgresql: INSERT INTO … (SELECT * …)
...d, time FROM tblB')
AS t(id integer, time integer)
WHERE time > 1000;
TABLE tblA;
id | time
----+------
1 | 5000
2 | 2000
(2 rows)
PostgreSQL has record pseudo-type (only for function's argument or result type), which allows you query data from another (unknown) table.
Edit:
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...验证中表现最好的。jmp0xf 译自Edwin Chen
How do you know what machine learning algorithm to choose for your classification problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each alg...
如何选择机器学习算法 - 大数据 & AI - 清泛网移动版 - 专注IT技能提升
...验证中表现最好的。jmp0xf 译自Edwin Chen
How do you know what machine learning algorithm to choose for your classification problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each alg...
如何选择机器学习算法 - 大数据 & AI - 清泛网移动版 - 专注IT技能提升
...验证中表现最好的。jmp0xf 译自Edwin Chen
How do you know what machine learning algorithm to choose for your classification problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each alg...
如何选择机器学习算法 - 大数据 & AI - 清泛网移动版 - 专注IT技能提升
...验证中表现最好的。jmp0xf 译自Edwin Chen
How do you know what machine learning algorithm to choose for your classification problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each alg...
如何选择机器学习算法 - 大数据 & AI - 清泛网移动版 - 专注IT技能提升
...验证中表现最好的。jmp0xf 译自Edwin Chen
How do you know what machine learning algorithm to choose for your classification problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each alg...