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What is Normalisation (or Normalization)?
...1 | Toyota
2 | Ford,Cadillac
Here the "Car" column (which is a string) have several values. That offends the first normal form, which says that each cell should have only one value. We can normalize this problem away by have a separate row per car:
UserId | Car
---------------------
1 ...
What is the dual table in Oracle?
...of dummy table with a single record used for selecting when you're not actually interested in the data, but instead want the results of some system function in a select statement:
e.g. select sysdate from dual;
See http://www.adp-gmbh.ch/ora/misc/dual.html
...
Global variables in Java
...is to create an interface like this:
public interface GlobalConstants
{
String name = "Chilly Billy";
String address = "10 Chicken head Lane";
}
Any class that needs to use them only has to implement the interface:
public class GlobalImpl implements GlobalConstants
{
public GlobalImpl()
...
How to format date and time in Android?
...the Android class and therefore there aren't any ambiguous classes. final String dateStr = DateFormat.getDateFormat(this).format(d); You can use Android's format() method and have (IMHO) cleaner code and one less Object to instantiate.
– Jerry Brady
Aug 22 '1...
How to ISO 8601 format a Date with Timezone Offset in JavaScript?
...all browsers (thanks to @MattJohnson for the tip)
Date.prototype.toIsoString = function() {
var tzo = -this.getTimezoneOffset(),
dif = tzo >= 0 ? '+' : '-',
pad = function(num) {
var norm = Math.floor(Math.abs(num));
return (norm < 10 ? '0'...
Include headers when using SELECT INTO OUTFILE?
... and combine files into one CSV file:
CSVHEAD=`/usr/bin/mysql $CONNECTION_STRING -e "$QUERY limit 1;"|head -n1|xargs|sed -e "s/ /'\;'/g"`
echo "\'$CSVHEAD\'" > $TMP/head.txt
/usr/bin/mysql $CONNECTION_STRING -e "$QUERY into outfile '${TMP}/data.txt' fields terminated by ';' optionally enclosed b...
Difference between static and shared libraries?
...
Shared libraries are .so (or in Windows .dll, or in OS X .dylib) files. All the code relating to the library is in this file, and it is referenced by programs using it at run-time. A program using a shared library only makes reference to the code that it uses in the shared library.
Static librar...
Ruby optional parameters
...cope ||= LDAP::LDAP_SCOPE_SUBTREE
... do something ...
end
Now if you call the method as above, the behaviour will be as you expect.
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How do I call a dynamically-named method in Javascript?
I am working on dynamically creating some JavaScript that will be inserted into a web page as it's being constructed.
9 An...
How to paginate with Mongoose in Node.js?
...this case, you can add the query page and/ or limit to your URL as a query string.
For example:
?page=0&limit=25 // this would be added onto your URL: http:localhost:5000?page=0&limit=25
Since it would be a String we need to convert it to a Number for our calculations. Let's do it using...