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MySQL - How to select data by string length

... select LENGTH('Ö'); results 2!! András Szepesházi's answer is the correct one! – fubo Oct 24 '13 at 13:59 ...
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Getting Python error “from: can't read /var/mail/Bio”

...xecute it as python script.py, otherwise the default shell will execute it and it will bail out at the from keyword. (Incidentally, from is the name of a command line utility which prints names of those who have sent mail to the given username, so that's why it tries to access the mailboxes). Anoth...
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How do I open links in Visual Studio in my web browser and not in Visual Studio?

...swer. Sub OpenURLInChrome() 'copy to end of line DTE.ActiveDocument.Selection.EndOfLine(True) 'set var Dim url As String = DTE.ActiveDocument.Selection.Text 'launch chrome with url System.Diagnostics.Process.Start( _ Environment.GetFolderPath(Environment.SpecialFolder.Local...
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select、poll、epoll之间的区别总结[整理] - C/C++ - 清泛网 - 专注C/C++及内核技术

select、poll、epoll之间的区别总结[整理]select,poll,epoll都是IO多路复用的机制。I O多路复用就通过一种机制,可以监视多个描述符,一旦某个描述符就绪(一般是读就绪或者写就绪...select,poll,epoll都是IO多路复用的机制。I/O多路...
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Pip install Matplotlib error with virtualenv

... Building Matplotlib requires libpng (and freetype, as well) which isn't a python library, so pip doesn't handle installing it (or freetype). You'll need to install something along the lines of libpng-devel and freetype-devel (or whatever the equivalent is for...
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Dynamic SELECT TOP @var In SQL Server

... SELECT TOP (@count) * FROM SomeTable This will only work with SQL 2005+ share | improve this answer | ...
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How to see query history in SQL Server Management Studio

...been evicted, etc.), you may be able to find the query in the plan cache. SELECT t.[text] FROM sys.dm_exec_cached_plans AS p CROSS APPLY sys.dm_exec_sql_text(p.plan_handle) AS t WHERE t.[text] LIKE N'%something unique about your query%'; If you lost the file because Management Studio crashed, you...
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Difference between 2 dates in SQLite

... SELECT julianday('now') - julianday(DateCreated) FROM Payment; share | improve this answer | follo...
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Is volatile expensive?

...LoadLoad or a LoadStore barrier. Further down the page I see that LoadLoad and LoadStore are effectively no-ops on X86 CPUs. Does this mean that volatile read operations can be done without a explicit cache invalidation on x86, and is as fast as a normal variable read (disregarding the reordering co...
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Ruby Arrays: select(), collect(), and map()

...re, to check the :qty key, you'd do something like the following: details.select{ |item| item[:qty] != "" } That will give you all items where the :qty key isn't an empty string. official select documentation share ...