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How do SQL EXISTS statements work?
I'm trying to learn SQL and am having a hard time understanding EXISTS statements. I came across this quote about "exists" and don't understand something:
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Sorting multiple keys with Unix sort
...s that need to be sorted by 1-n keys. Some of these keys might be numeric and some of them might not be. This is a fixed-width columnar file so there are no delimiters.
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Why does typeof NaN return 'number'?
...eration
which return NaN:
Operations with a NaN as at least one operand
Indeterminate forms
The divisions 0/0, ∞/∞, ∞/−∞, −∞/∞, and −∞/−∞
The multiplications 0×∞ and 0×−∞
The power 1^∞
The additions ∞ + (−∞), (−∞) + ∞ and e...
Examples of Algorithms which has O(1), O(n log n) and O(log n) complexities
What are some algorithms which we use daily that has O(1), O(n log n) and O(log n) complexities?
11 Answers
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What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
...mbers as floats, this allows scientific notation eg 1.234E10 but is slower and subject to rounding error (1.2345678 could come after 1.2345679), numeric sort is just a regular alphabetic sort that knows 10 comes after 9.
See http://www.gnu.org/software/coreutils/manual/html_node/sort-invocatio...
Hibernate, @SequenceGenerator and allocationSize
...nce by one , multiple this value by 50 (default allocationSize value) - and then uses this value as entity ID.
6 Answers...
How to sleep for five seconds in a batch file/cmd [duplicate]
...ds, such as taking an image being displayed by the webcam. (Run the script and smile at the camera, for example.)
30 Answer...
Regular expression that matches valid IPv6 addresses
...ular expressions, so I wrote one that works with POSIX regular expressions and PERL regular expressions.
It should match:
IPv6 addresses
zero compressed IPv6 addresses (section 2.2 of rfc5952)
link-local IPv6 addresses with zone index (section 11 of rfc4007)
IPv4-Embedded IPv6 Address (section 2 ...
What is a non-capturing group in regular expressions?
How are non-capturing groups, i.e. (?:) , used in regular expressions and what are they good for?
15 Answers
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How to strip all non-alphabetic characters from string in SQL Server?
...t dbo.RemoveNonAlphaCharacters('abc1234def5678ghi90jkl')
Once you understand the code, you should see that it is relatively simple to change it to remove other characters, too. You could even make this dynamic enough to pass in your search pattern.
Hope it helps.
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