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SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
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update q
set q.QuestionID = a.QuestionID
from QuestionTrackings q
inner join QuestionAnswers a
on q.AnswerID = a.AnswerID
where q.QuestionID is null -- and other conditions you might want
I recommend to check what the result set to update is befo...
NTFS performance and large volumes of files and directories
How does Windows with NTFS perform with large volumes of files and directories?
7 Answers
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How could the UNIX sort command sort a very large file?
The UNIX sort command can sort a very large file like this:
7 Answers
7
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How to combine paths in Java?
...hing string-based, you should use a class which is designed to represent a file system path.
If you're using Java 7 or Java 8, you should strongly consider using java.nio.file.Path; Path.resolve can be used to combine one path with another, or with a string. The Paths helper class is useful too. Fo...
What's the difference between identifying and non-identifying relationships?
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An identifying relationship is when the existence of a row in a child table depends on a row in a parent table. This may be confusing because it's common practice these days to create a pseudokey for a child table, but not make...
Locking a file in Python
I need to lock a file for writing in Python. It will be accessed from multiple Python processes at once. I have found some solutions online, but most fail for my purposes as they are often only Unix based or Windows based.
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How to read a large file line by line?
I want to read a file line by line, but without completely loading it in memory.
14 Answers
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How to check if a folder exists
... with the new Java 7 IO features, actually I trying to receive all the xml files of a folder. But this throws an exception when the folder does not exist, how can I check if the folder exists with the new IO?
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How do you tell Resharper that a method parameter is a string containing a CSS class?
...ce it won't have all the CSS classes used by the app across all of its CSS files.
– Raif Atef
Jan 24 '16 at 21:22
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Difference between modes a, a+, w, w+, and r+ in built-in open function?
...s (Additional characters may follow these sequences.):
``r'' Open text file for reading. The stream is positioned at the
beginning of the file.
``r+'' Open for reading and writing. The stream is positioned at the
beginning of the file.
``w'' Truncate file to zero lengt...