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generate days from date range
...es, or temp tables. The subquery generates dates for the last 10,000 days, and could be extended to go as far back or forward as you wish.
select a.Date
from (
select curdate() - INTERVAL (a.a + (10 * b.a) + (100 * c.a) + (1000 * d.a) ) DAY as Date
from (select 0 as a union all select 1 un...
What does value & 0xff do in Java?
... not quite. The & operator works on long values as well, if either operand is a long. But not on byte. See the Java Language Specification, sections 15.22.1 and 5.6.2.
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Find row where values for column is maximal in a pandas DataFrame
...
Use the pandas idxmax function. It's straightforward:
>>> import pandas
>>> import numpy as np
>>> df = pandas.DataFrame(np.random.randn(5,3),columns=['A','B','C'])
>>> df
A B ...
Purpose of Unions in C and C++
...ed unions earlier comfortably; today I was alarmed when I read this post and came to know that this code
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Post Build exited with code 1
...
She had a space in one of the folder names in her path, and no quotes around it.
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Remove all the elements that occur in one list from another
Let's say I have two lists, l1 and l2 . I want to perform l1 - l2 , which returns all elements of l1 not in l2 .
7 ...
Declaring and initializing variables within Java switches
... block in which the declaration appears, starting with its own initializer and including any further declarators to the right in the local variable declaration statement.
In your case, case 2 is in the same block as case 1 and appears after it, even though case 1 will never execute... so the local...
Pretty graphs and charts in Python [closed]
What are the available libraries for creating pretty charts and graphs in a Python application?
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Cleaner way to update nested structures
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Zippers
Huet's Zipper provides convenient traversal and 'mutation' of an immutable data structure. Scalaz provides Zippers for Stream (scalaz.Zipper), and Tree (scalaz.TreeLoc). It turns out that the structure of the zipper is automatically derivable from the original data str...
Database Design for Revisions?
...tribute. This just causes problems down the line, requires surrogate keys and all sorts of other problems.
Design 2 does have problems with schema changes. If you change the Employees table you have to change the EmployeeHistories table and all the related sprocs that go with it. Potentially doub...