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SQL - Update multiple records in one query
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177
Try either multi-table update syntax
UPDATE config t1 JOIN config t2
ON t1.config_name =...
How do I retrieve the number of columns in a Pandas data frame?
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312
Like so:
import pandas as pd
df = pd.DataFrame({"pear": [1,2,3], "apple": [2,3,4], "orange": [...
Using build types in Gradle to run same app that uses ContentProvider on one device
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14 Answers
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How to get a variable name as a string in PHP?
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edited Nov 1 '08 at 1:11
answered Nov 1 '08 at 0:42
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For i = 0, why is (i += i++) equal to 0?
...; // i=0 because the ++ is a postfix operator and hasn't been executed
i + 1; // Note that you are discarding the calculation result
What actually happens is more involved than that - take a look at MSDN, 7.5.9 Postfix increment and decrement operators:
The run-time processing of a postfix inc...
Modulo operation with negative numbers
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How to create a temporary directory?
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answered Jan 8 '11 at 2:30
moinudinmoinudin
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How to print to console in pytest?
...n that particular test.
For example,
def test_good():
for i in range(1000):
print(i)
def test_bad():
print('this should fail!')
assert False
Results in the following output:
>>> py.test tmp.py
============================= test session starts ======================...
How can I create a correlation matrix in R?
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104
An example,
d &lt- data.frame(x1=rnorm(10),
x2=rnorm(10),
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How to echo or print an array in PHP?
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11 Answers
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