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Multiple Updates in MySQL
...has new records then i will end up inserting only the ids and count except all other information. if and only if there is an entry for the id then it should update else it should skip. what shall i do?
– Jayapal Chandran
Aug 30 '10 at 13:30
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Optional Parameters in Go?
...eah, except the notion of "zero value" is absolutely useless for int/float/string types, because those values are meaningful and so you can't tell the difference if the value was omitted from the struct or if zero value was passed intentionally.
– keymone
Mar 2...
Openssl is not recognized as an internal or external command
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Well at the place of openssl ... you have to put actually the path to your openssl folder that you have downloaded. Your actual command should look like:
keytool -exportcert -alias androiddebugkey -keystore ~/.android/debug.keystore | "C:\Users\abc\openssl\bin\openssl.exe" sha1...
How do I install an R package from source?
...nt me along this great tutorial on webscraping NYtimes with R . I would really love to try it. However, the first step is to installed a package called RJSONIO from source.
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SQL Server Installation - What is the Installation Media Folder?
I am installing SQL Server 2008. I have installed .NET framework 3.5.
Then I got folder SQL Server 2008 and performed following steps-
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What's an easy way to read random line from a file in Unix command line?
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You can use shuf:
shuf -n 1 $FILE
There is also a utility called rl. In Debian it's in the randomize-lines package that does exactly what you want, though not available in all distros. On its home page it actually recommends the use of shuf instead (which didn't exist when it was cr...
SQLAlchemy - Getting a list of tables
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All of the tables are collected in the tables attribute of the SQLAlchemy MetaData object. To get a list of the names of those tables:
>>> metadata.tables.keys()
['posts', 'comments', 'users']
If you're using the...
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'...
UIBarButtonItem with custom image and no border
...ation code here
}
@end
So anywhere in your code you can create bar item calling this method (provided that you include a header with its declaration).
P.S. You do not need to use 'v' UIView as you can create UIBarButtonItem with a button as custom view directly.
P.P.S. You also need [forward rel...
Add legend to ggplot2 line plot
...t each line is given a color by mapping the colour aesthetic to a constant string. Choosing the string which is what you want to appear in the legend is the easiest. The fact that in this case it is the same as the name of the y variable being plotted is not significant; it could be any set of strin...