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Is it expensive to use try-catch blocks even if an exception is never thrown?
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try has almost no expense at all. Instead of doing the work of setting up the try at runtime, the code's metadata is structured at compile time such that when an exception is thrown, it now does a relatively expensive operation of walking up the stack and seeing if any try blocks exist t...
Markdown and including multiple files
Is there any markdown fork that allows you to reference other files, something like an includes file? Specifically, I want to create a separate markdown file with links that I call often but not always (call this B.md), then when I link by reference in the md file I'm writing (A.md), I'd like it to ...
Web workers without a separate Javascript file?
As far as I can tell, web workers need to be written in a separate JavaScript file, and called like this:
25 Answers
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How do I use the CONCAT function in SQL Server 2008 R2?
I was looking for a CONCAT function in SQL Server 2008 R2. I found the link for this function . But when I use this function, it gives the following error:
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Mean per group in a data.frame [duplicate]
... of columns, you could first get the names of all the numeric columns, and set those with .SDcols = numericVars, instead of having to try to name them all in the j column. Another instance is using := to assign values in place .SD := lapply(.SD, f)
– cnolte
Jul...
How to implement a many-to-many relationship in PostgreSQL?
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Cannot open database “test” requested by the login. The login failed. Login failed for user 'xyz\ASP
..."xyz\ASPNET" is not a login (in sys.server_principals)
Or: "xyz\ASPNET" is set up but not mapped to a user in the database test (sys.database_principals)
I'd go for the 2nd option: the error message implies the default database is either not there or no rights in it, rather than not set up as a lo...
Making an iframe responsive
I was reading this stackoverflow post titled "Can you make an iFrame responsive?", and one of the comments/answers led me to this jfiddle.
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Jackson - Deserialize using generic class
...not access private java.lang.class.Class() from java.lang.class. Failed to set access. Cannot make a java.lang.Class constructor accessible
– gnjago
Jul 26 '12 at 19:46
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Image comparison - fast algorithm
I'm looking to create a base table of images and then compare any new images against that to determine if the new image is an exact (or close) duplicate of the base.
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