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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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What is the difference between typeof and instanceof and when should one be used vs. the other?
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@Luke generally a bad idea to use "new String" like this. that creates a "string object" rather than a string primitive. see section here developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…
– Colin D
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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...
What is Unicode, UTF-8, UTF-16?
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Why do we need Unicode?
In the (not too) early days, all that existed was ASCII. This was okay, as all that would ever be needed were a few control characters, punctuation, numbers and letters like the ones in this sentence. Unfortunately, today's strange world of global interc...
Do I have to guard against SQL injection if I used a dropdown?
... make sure the posted size is what you expect.
$possibleOptions = array('All', 'Large', 'Medium', 'Small');
if(in_array($_POST['size'], $possibleOptions)) {
// Expected
} else {
// Not Expected
}
Then use mysqli_* if you are using a version of php >= 5.3.0 which you should be, to sav...
How does one create an InputStream from a String? [duplicate]
...may not be the one you want here). For me, this is UTF-8 (which can encode all Java Strings). The right answer would be "indicate the encoding you really want", not "use UTF-16". And you can use it with .getBytes(charsetName), don't have to explicitly create a Charset object and encode the String to...
Convert pem key to ssh-rsa format
...m assuming no password for the keys (which is bad).
Generate an RSA pair
All the following methods give an RSA key pair in the same format
With openssl (man genrsa)
openssl genrsa -out dummy-genrsa.pem 2048
In OpenSSL v1.0.1 genrsa is superseded by genpkey so this is the new way to do it (man...
How can I get the list of files in a directory using C or C++?
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In small and simple tasks I do not use boost, I use dirent.h which is also available for windows:
DIR *dir;
struct dirent *ent;
if ((dir = opendir ("c:\\src\\")) != NULL) {
/* print all the files and directories within director...
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'...
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...