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What makes a SQL statement sargable?
...L optimizer can't use an index on myDate, even if one exists. It will literally have to evaluate this function for every row of the table. Much better to use:
WHERE myDate >= '01-01-2008' AND myDate < '01-01-2009'
Some other examples:
Bad: Select ... WHERE isNull(FullName,'Ed Jones') = 'Ed...
Filtering for empty or NULL names in a queryset
...lias (optional) which I need to search for. So, I need a query to give me all the names that have an alias set.
7 Answers
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Subset of rows containing NA (missing) values in a chosen column of a data frame
...ated. THe point is to use is.na, I wrongly interpreted you wanted to check all variables.
– Joris Meys
Nov 2 '11 at 21:34
3
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Difference between document.addEventListener and window.addEventListener?
...o events destined for a different object. You should use the one that actually has the event you are interested in.
For example, there is a "resize" event on the window object that is not on the document object.
For example, the "DOMContentLoaded" event is only on the document object.
So basical...
How to keep the local file or the remote file during merge using Git and the command line?
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This approach seems more straightforward, avoiding the need to individually select each file:
# keep remote files
git merge --strategy-option theirs
# keep local files
git merge --strategy-option ours
or
# keep remote files
git pull -Xtheirs
# keep local files
git pull -Xours
Copied direct...
Is Dvorak typing appropriate for programming? [closed]
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There are Dvorak layouts specifically for programming: http://www.kaufmann.no/roland/dvorak/
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Regular expressions in C: examples?
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Regular expressions actually aren't part of ANSI C. It sounds like you might be talking about the POSIX regular expression library, which comes with most (all?) *nixes. Here's an example of using POSIX regexes in C (based on this):
#include <reg...
Should CSS always preceed Javascript?
...e recommendation to include CSS prior to JavaScript. The reasoning is generally, of this form :
14 Answers
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How to prevent http file caching in Apache httpd (MAMP)
...d this? Should work in both .htaccess, httpd.conf and in a VirtualHost (usually placed in httpd-vhosts.conf if you have included it from your httpd.conf)
<filesMatch "\.(html|htm|js|css)$">
FileETag None
<ifModule mod_headers.c>
Header unset ETag
Header set Cache-Control "m...
What does the “yield” keyword do?
... list, you can read its items one by one. Reading its items one by one is called iteration:
>>> mylist = [1, 2, 3]
>>> for i in mylist:
... print(i)
1
2
3
mylist is an iterable. When you use a list comprehension, you create a list, and so an iterable:
>>> mylist = [...