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how do I query sql for a latest record date for each user
... date,
value,
row_number() over(partition by username order by date desc) as rn
from
yourtable
) t
where t.rn = 1
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Disable ONLY_FULL_GROUP_BY
...ution): you have to put the description of sql_mode inside a my.cnf file (/etc/my.cnf for instance) and restart the server. For instance, insert (below the [mysqld] section) sql_mode = "STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITU...
Git Bash is extremely slow on Windows 7 x64
... performance problems. To fix permanently, edit C:\Program Files (x86\Git\etc\profile and comment out the if-then-else where __git_ps1 is added to PS1.
– Tom
Jun 29 '15 at 11:12
7...
How to pass anonymous types as parameters?
...passed around, a more structured way may / should normally be preferred in order to not introduce hard to find bugs (you're sidestepping the type system). However, if you want to find a compromise, another way is to simply pass a generic Dictionary. C# dictionary initializers are pretty convenient t...
How to make an HTTP POST web request
...to add that the response variable for the POST request is a byte array. In order to get the string response you just do Encoding.ASCII.GetString(response); (using System.Text)
– Sindre
Jan 17 '14 at 19:52
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css z-index lost after webkit transform translate3d
... So in "preserve-3d" mode we gotta use z-axis of transform to set order, and in flat mode we should use z-index. The bug is that z-index on safari is broken in combination with HW accelerated transforms.
– Steven Lu
Jan 27 '13 at 17:56
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Sort ArrayList of custom Objects by property
... above the other answer is beyond me. This link may also be useful: Object Ordering Tutorial at Sun.com.
– BalusC
May 6 '10 at 21:26
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What's the difference between a continuation and a callback?
... misapprehensions:
Tail call optimisation is not by any means required in order to support first-class continuations. Consider that even the C language has a (restricted) form of continuations in the form of setjmp(), which creates a continuation, and longjmp(), which invokes one!
On the other ha...
Effects of the extern keyword on C functions
...tion. It is ugly, and unnecessary 99.99% of the time (I could be off by an order or two or magnitude, overstating how often it is necessary). It usually occurs when people misunderstand that a header is only needed when other source files will use the information; the header is (ab)used to store de...
What does “#define _GNU_SOURCE” imply?
... Of course, everyone knows the real reason to define _GNU_SOURCE is in order to get strfry and memfrob.
– user4815162342
Mar 9 '13 at 20:40
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