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Java: Instanceof and Generics
Before I look through my generic data structure for a value's index, I'd like to see if it is even an instance of the type this has been parametrized to.
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SQL: How to properly check if a record exists
...ther of the following:
-- Method 1.
SELECT 1
FROM table_name
WHERE unique_key = value;
-- Method 2.
SELECT COUNT(1)
FROM table_name
WHERE unique_key = value;
The first alternative should give you no result or one result, the second count should be zero or one.
How old is the documentation you'r...
Git - fatal: Unable to create '/path/my_project/.git/index.lock': File exists
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Try
rm -f ./.git/index.lock
In your repository directory. The error message is rather explicit as to what causes it typically, so if you have no other git processes running (which is the normal case), go ahead and delete that file.
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nvm keeps “forgetting” node in new terminal session
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dylantsdylants
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Practical use of `stackalloc` keyword
Has anyone ever actually used stackalloc while programming in C#? I am aware of what is does, but the only time it shows up in my code is by accident, because Intellisense suggests it when I start typing static , for example.
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MySQL ON DUPLICATE KEY - last insert id?
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Check this page out: https://web.archive.org/web/20150329004325/https://dev.mysql.com/doc/refman/5.0/en/insert-on-duplicate.html
At the bottom of the page they explain how you can make LAST_INSERT_ID meaningful for updates by pas...
Word-wrap in an HTML table
I've been using word-wrap: break-word to wrap text in div s and span s. However, it doesn't seem to work in table cells. I have a table set to width:100% , with one row and two columns. Text in columns, although styled with the above word-wrap , doesn't wrap. It causes the text to go past the ...
Finding the max/min value in an array of primitives using Java
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Maarten Bodewes
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answered Sep 28 '09 at 8:43
Michael Rutherf...
Can you make valid Makefiles without tab characters?
On my system (Mac OS X), make seems to require that that Makefiles have a tab character preceding the the content of each command line, or it throws a syntax error.
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Any shortcut to initialize all array elements to zero?
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Michael BorgwardtMichael Borgwardt
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