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MySQL order by before group by
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Using an ORDER BY in a subquery is not the best solution to this problem.
The best solution to get the max(post_date) by author is to use a subquery to return the max date and then join that to your table on both the post_author an...
Reminder - \r\n or \n\r?
...ater look at a PC keyboard, see the key called "Enter," and get the letter order wrong!
– Rob Kennedy
Jun 30 '11 at 19:36
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Rolling median algorithm in C
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I couldn't find a modern implementation of a c++ data structure with order-statistic so ended up implementing both ideas in top coders link suggested by MAK ( Match Editorial: scroll down to FloatingMedian).
Two multisets
The first idea partitions the data into two data structures (heaps, mu...
Web Service vs WCF Service
...nce of DataContractSerializer and XmlSerializer is that DCS requires field ordering - which is why I don't use DCS for non-transient serialization or contracts! Thus it's possible to break a service used by clients not using the fixed ordering when moving to DCS (or moving to DCS but in a different ...
nginx error connect to php5-fpm.sock failed (13: Permission denied)
... socket, if one is used. In Linux, read/write
; permissions must be set in order to allow connections from a web server. Many
; BSD-derived systems allow connections regardless of permissions.
; Default Values: user and group are set as the running user
; mode is set to 0660
;listen...
MIN/MAX vs ORDER BY and LIMIT
...ay' and 'NULL' rows) whereas the SORT and LIMIT still needs needs to do an ordered traversal of the index (106,000 rows). The actual performance impact is probably negligible.
It looks like MIN() is the way to go - it's faster in the worst case, indistinguishable in the best case, is standard SQL ...
How to convert an OrderedDict into a regular dict in python3
I am struggling with the following problem:
I want to convert an OrderedDict like this:
8 Answers
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Encapsulation vs Abstraction?
...escribing something in simpler terms, i.e abstracting away the details, in order to focus on what is important (This is also seen in abstract art, for example, where the artist focuses on the building blocks of images, such as colour or shapes). The same idea translates to OOP by using an inheritan...
JPA eager fetch does not join
...loading when constructing a customer class with a collection for customer orders. If you retrieved every order for a customer when you wanted to get a customer list this may be a expensive database operation when you only looking for customer name and contact details. Best to leave the db access ti...
string.ToLower() and string.ToLowerInvariant()
...d is recommended when a collection of strings must appear in a predictable order in a user interface control.
also
...ToLower is very similar in most places to ToLowerInvariant. The documents indicate that these methods will only change behavior with Turkish cultures. Also, on Windows systems...