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What is the meaning of the term arena in relation to memory?
...ost importantly, it requires platform-specific knowledge to get the memory ordering right. I use "magic" for things that can either not be written portably by the user at all (like an efficient mutex, or tcmalloc, or the type name of a lambda), or only with extreme heroics (like std::function); I do...
Sort a Map by values
...dHashMap is important to the solution as it provides predictable iteration order.
– Carter Page
Jul 1 '12 at 12:46
3
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How to use Oracle ORDER BY and ROWNUM correctly?
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The where statement gets executed before the order by. So, your desired query is saying "take the first row and then order it by t_stamp desc". And that is not what you intend.
The subquery method is the proper method for doing this in Oracle.
If you want a version ...
How to get next/previous record in MySQL?
...o cemkalyoncu's solution:
next record:
SELECT * FROM foo WHERE id > 4 ORDER BY id LIMIT 1;
previous record:
SELECT * FROM foo WHERE id < 4 ORDER BY id DESC LIMIT 1;
edit: Since this answer has been getting a few upvotes lately, I really want to stress the comment I made earlier about un...
SQL Group By with an Order By
... all versions of MySQL, simply alias the aggregate in the SELECT list, and order by the alias:
SELECT COUNT(id) AS theCount, `Tag` from `images-tags`
GROUP BY `Tag`
ORDER BY theCount DESC
LIMIT 20
share
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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
...
What JSON library to use in Scala? [closed]
....
There are quite a variety of alternatives. I list them in no particular order, with notes:
parsing.json.JSON - Warning this library is available only up to Scala version 2.9.x (removed in newer versions)
spray-json - Extracted from the Spray project
Jerkson ± - Warning a nice library (built on...
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...
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...
Implement paging (skip / take) functionality with this query
... 2012 it is very very easy
SELECT col1, col2, ...
FROM ...
WHERE ...
ORDER BY -- this is a MUST there must be ORDER BY statement
-- the paging comes here
OFFSET 10 ROWS -- skip 10 rows
FETCH NEXT 10 ROWS ONLY; -- take 10 rows
If we want to skip ORDER BY we can use
SELECT col1, col...