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Insert, on duplicate update in PostgreSQL?
... edited May 23 '17 at 11:54
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answered Jul 10 '09 at 12:18
Stephen DenneStephe...
What causes and what are the differences between NoClassDefFoundError and ClassNotFoundException?
...ed-for class definition
existed when the currently executing
class was compiled, but the definition
can no longer be found.
So, it appears that the NoClassDefFoundError occurs when the source was successfully compiled, but at runtime, the required class files were not found. This may be some...
How to create a generic array in Java?
...")
final E e = (E) a[i];
return e;
}
}
Note that the component type of the array should be the erasure of the type parameter:
public class GenSet<E extends Foo> { // E has an upper bound of Foo
private Foo[] a; // E erases to Foo, so use Foo[]
public GenSet(int...
Retrieving the last record in each group - MySQL
...150) NOT NULL default '',
`AnswerCount` int(11) NOT NULL default '0',
`CommentCount` int(11) NOT NULL default '0',
`FavoriteCount` int(11) NOT NULL default '0',
`ClosedDate` datetime default NULL,
PRIMARY KEY (`PostId`),
UNIQUE KEY `PostId` (`PostId`),
KEY `PostTypeId` (`PostTypeId`),...
Download file from an ASP.NET Web API method using AngularJS
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Set environment variables on Mac OS X Lion
...ze about OS X is that it is built on Unix. This is where the .bash_profile comes in. When you start the Terminal app in OS X you get a bash shell by default. The bash shell comes from Unix and when it loads it runs the .bash_profile script. You can modify this script for your user to change your set...
What is a None value?
...the sticker on None.
So that's all that's going on. In reality, Python comes with some stickers already attached to objects (built-in names), but others you have to write yourself with lines like F = "fork" and A = 2 and c17 = 3.14, and then you can stick them on other objects later (like F = 10...
Find a value anywhere in a database
...tring
-- Written by: Narayana Vyas Kondreddi
-- Site: http://vyaskn.tripod.com
-- Tested on: SQL Server 7.0 and SQL Server 2000
-- Date modified: 28th July 2002 22:50 GMT
DECLARE @Results TABLE(ColumnName nvarchar(370), ColumnValue nvarchar(3630))
SET NOCOUNT ON
DECLARE @TableName nvarchar(256), ...
Throwing cats out of windows
... and still m cats.
The worst case of two should be chosen, hence max.
+ 1 comes from the fact that we've just used one attempt (regardless of whether cat has survived or not).
We try every possible floor to find the best result, hence min(f(k)) : for k in 1..n.
It agrees with Google result from G...
Elegant ways to support equivalence (“equality”) in Python classes
...n2 # False -- oops
So, Python by default uses the object identifiers for comparison operations:
id(n1) # 140400634555856
id(n2) # 140400634555920
Overriding the __eq__ function seems to solve the problem:
def __eq__(self, other):
"""Overrides the default implementation"""
if isinstance...