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MIN/MAX vs ORDER BY and LIMIT
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In the worst case, where you're looking at an unindexed field, using MIN() requires a single full pass of the table. Using SORT and LIMIT requires a filesort. If run against a large table, there would likely be a significant difference in percieved performance. As a mea...
Get the first item from an iterable that matches a condition
...tant that the resulting method not process the entire list, which could be quite large. For example, the following function is adequate:
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How to change font face of Webview in Android?
...k for me in android 5.1 . I used (Dan Syrstad)'s answer. the difference is quotation font-family: 'myface';
– Mneckoee
Nov 15 '16 at 11:35
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What is the difference between JVM, JDK, JRE & OpenJDK?
... the Oracle JDK and the OpenJDK.
The differences are stated in this blog:
Q: What is the difference between the source code found in the OpenJDK repository, and the code you use to build the Oracle JDK?
A: It is very close - our build process for Oracle JDK releases builds on OpenJDK 7 by adding ju...
How to read a text file into a list or an array with Python
...ist_of_lists) returns a zip object that is not subscriptable.
If you need indexed access you can use
by_cols = list(zip(*list_of_lists))
that gives you a list of lists in both versions of Python.
On the other hand, if you don't need indexed access and what you want is just to build a dictionary...
Proper indentation for Python multiline strings
...parts you don't need, you should consider the textwrap module or the technique for postprocessing docstrings presented in PEP 257:
def trim(docstring):
if not docstring:
return ''
# Convert tabs to spaces (following the normal Python rules)
# and split into a list of lines:
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Selenium wait until document is ready
...tion. You catch the exception and do your needs. I am not sure whether it quits the page loading after the exception thrown. i didn't try this code yet. Want to just try it.
This is an implicit wait. If you set this once it will have the scope until the Web Driver instance destroy.
See the docume...
Is there a python equivalent of Ruby's 'rvm'?
Q: Do we have anything functionally equivalent in Python to the Ruby version manager 'rvm' ?
6 Answers
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How to print third column to last column?
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awk '{ print substr($0, index($0,$3)) }'
solution found here:
http://www.linuxquestions.org/questions/linux-newbie-8/awk-print-field-to-end-and-character-count-179078/
sha...
MongoDB logging all queries
...t(5) as well to see less/more queries.
$nin - will filter out profile and indexes queries
Also, use the query projection {'query':1} for only viewing query field
db.system.profile.find(
{
ns: {
$nin : ['meteor.system.profile','meteor.system.indexes']
}
}
).limit(5).sort( { ts ...