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How to copy a row and insert in same table with a autoincrement field in MySQL?
....)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SELECT:
insert into your_table (id, c1, c2, ...)
select 2, c1, c2, ...
from your_table
where i...
Get Image size WITHOUT loading image into memory
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As the comments allude, PIL does not load the image into memory when calling .open. Looking at the docs of PIL 1.1.7, the docstring for .open says:
def open(fp, mode="r"):
"Open an image file, without loading the raster data"
There ar...
PhoneGap: Detect if running on desktop browser
...he 'desktop' and mobile versions. I want to be able to detect if PhoneGap calls will work (ie, is the user on a mobile device that will support PhoneGap).
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Python extract pattern matches
...h a standard python REPL, the last result is stored in a special variable called _. It isn't valid outside anywhere else.
– UltraInstinct
Mar 13 '19 at 2:25
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Which SQL query is faster? Filter on Join criteria or Where clause?
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Performance-wise, they are the same (and produce the same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = ...
How do I get indices of N maximum values in a NumPy array?
...t been able to find one.
If this solution turns out to be too slow (especially for small n), it may be worth looking at coding something up in Cython.
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Remove all special characters with RegExp
I would like a RegExp that will remove all special characters from a string. I am trying something like this but it doesn’t work in IE7, though it works in Firefox.
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PHP: Convert any string to UTF-8 without knowing the original character set, or at least try
I have an application that deals with clients from all over the world, and, naturally, I want everything going into my databases to be UTF-8 encoded.
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Installing older version of R package
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To install an older version of a package from source (within R):
packageurl <- "http://cran.r-project.org/src/contrib/Archive/ggplot2/ggplot2_0.9.1.tar.gz"
install.packages(packageurl, repos=NULL, type="source")
If this doesn'...
Installing python module within code
I need to install a package from PyPi straight within my script.
Maybe there's some module or distutils ( distribute , pip etc.) feature which allows me to just execute something like pypi.install('requests') and requests will be installed into my virtualenv.
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