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Rails 3: Get Random Record
...
Thing.first(:order => "RANDOM()") # For MySQL :order => "RAND()", - thanx, @DanSingerman
# Rails 3
Thing.order("RANDOM()").first
or
Thing.first(:offset => rand(Thing.count))
# Rails 3
Thing.offset(rand(Thing.count)).first
Ac...
How to increment a NSNumber
...etter. They're more concise, and don't require additional variables.
In order to increment an NSNumber, you're going to have to get its value, increment that, and store it in a new NSNumber.
For instance, for an NSNumber holding an integer:
NSNumber *number = [NSNumber numberWithInt:...];
int v...
Is it possible to view RabbitMQ message contents directly from the command line?
...RabbitMQ queue to local files and requeuing the messages in their original order.
Example usage (to dump the first 50 messages of queue incoming_1):
rabbitmq-dump-queue -url="amqp://user:password@rabbitmq.example.com:5672/" -queue=incoming_1 -max-messages=50 -output-dir=/tmp
...
How can we match a^n b^n with Java regex?
...our definition of "good". For example the recursive solution is around one order of magnitude faster than the other one (codepad.viper-7.com/CWgy7c). And it is far easier to understand. The recursive solution is pretty much the direct transformation of the grammar into a regex (actually you could ju...
Row Offset in SQL Server
...2005+
SELECT col1, col2
FROM (
SELECT col1, col2, ROW_NUMBER() OVER (ORDER BY ID) AS RowNum
FROM MyTable
) AS MyDerivedTable
WHERE MyDerivedTable.RowNum BETWEEN @startRow AND @endRow
SQL Server 2000
Efficiently Paging Through Large Result Sets in SQL Server 2000
A More Efficient Method...
How to determine if a number is a prime with regex?
...to find some non empty sub-sequence that can be repeated at least twice in order to form the sequence. If such a subsequence exists, it means that its length divides N, hence N is not prime.
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Class.forName() vs ClassLoader.loadClass() - which to use for dynamic loading? [duplicate]
...oadClass("..."); on a Class type to attempt to load a Torque peer class in order to run a static initializer block which maps the peer to a database table. The static block was not executed on this call. However, upon calling Class.forName("..."); for the peer class the static block was executed. +1...
Using Git with an existing Xcode project
... process, mostly pieced together from the other answers on this page/site. Order is very important here
Open terminal and cd into the directory containing the .xcodeproj file
git init
In finder enter the newly created .git folder (in the same directory as the .xcodeproj file). Find info/exclude, o...
How to get the browser viewport dimensions?
... others) you must have the <!DOCTYPE html> at the top of the page in order for the code to work.
– Tzury Bar Yochay
May 9 '13 at 7:44
6
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SQL Query to concatenate column values from multiple rows in Oracle
...ommon one is to use LISTAGG:
SELECT pid, LISTAGG(Desc, ' ') WITHIN GROUP (ORDER BY seq) AS description
FROM B GROUP BY pid;
Then join to A to pick out the pids you want.
Note: Out of the box, LISTAGG only works correctly with VARCHAR2 columns.
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