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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...
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 ...
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...
What is an AngularJS directive?
...entation, directives are structures you can write that angularjs parses in order to create objects and behaviors.In other words it's a template in which you use mix of any arbitrary nodes and pseudo-javascript and placeholders for data to express intentions of how your widget (component) is structur...
In C/C++ what's the simplest way to reverse the order of bits in a byte?
While there are multiple ways to reverse bit order in a byte, I'm curious as to what is the "simplest" for a developer to implement. And by reversing I mean:
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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...
Unioning two tables with different number of columns
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I came here and followed above answer. But mismatch in the Order of data type caused an error. The below description from another answer will come handy.
Are the results above the same as the sequence of columns in your table? because oracle is strict in column orders. this example ...
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 ...
How can I autoformat/indent C code in vim?
...below, etc. All the options are controlled by command line parameters.
In order to use it in vim, just set the formatprg option to it, and then use the gq command. So, for example, I have in my .vimrc:
autocmd BufNewFile,BufRead *.cpp set formatprg=astyle\ -T4pb
so that whenever I open a .cpp fi...
sort object properties and JSON.stringify
... sometimes replaced, the properties on the objects are listed in different orders (their creation order?). When I do JSON.stringify() on the array and save it, a diff shows the properties getting listed in different orders, which is annoying when trying to merge the data further with diff and mergin...