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Find difference between timestamps in seconds in PostgreSQL
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Try:
SELECT EXTRACT(EPOCH FROM (timestamp_B - timestamp_A))
FROM TableA
Details here: EXTRACT.
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How to get scrollbar position with Javascript?
...roll position isn't set on document.body in most modern browsers - it's usually set on document.documentElement now. See bugs.chromium.org/p/chromium/issues/detail?id=157855 for Chrome's transition.
– fzzfzzfzz
May 3 '18 at 15:51
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More elegant “ps aux | grep -v grep”
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brilliant hack (I think I should call it that, since the aux / grep authors probably did not think of this scenario.)
– Michael Trouw
Apr 12 '16 at 14:12
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What does `unsigned` in MySQL mean and when to use it?
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MySQL says:
All integer types can have an optional
(nonstandard) attribute UNSIGNED.
Unsigned type can be used to permit
only nonnegative numbers in a column
or when you need a larger upper
numeric range for the column. For
e...
How to send HTML-formatted email? [duplicate]
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Setting isBodyHtml to true allows you to use HTML tags in the message body:
msg = new MailMessage("xxxx@gmail.com",
"yyyy@gmail.com", "Message from PSSP System",
"This email sent by the PSSP system<br />" +
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How to track child process using strace?
...ously search for the parent thread, then the grandparent thread, and so on all the way to the root process.
4 Answers
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How do you get the index of the current iteration of a foreach loop?
...or iterating over collections that implement IEnumerable. It does this by calling GetEnumerator on the collection, which will return an Enumerator.
This Enumerator has a method and a property:
MoveNext()
Current
Current returns the object that Enumerator is currently on, MoveNext updates Current t...
Is there an equivalent for var_dump (PHP) in Javascript?
...vidual property: some objects have a LOT of properties and you'll be there all day clicking "OK", "OK", "OK", "O... dammit that was the property I was looking for".
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leading zeros in rails
...using a given padding character.
str.rjust(integer, padstr=' ') → new_str
If integer is greater than the length of str, returns a new String of length integer with str right justified and padded with padstr; otherwise, returns str.
some_int = 5
some_int.to_s.rjust(2, '0') # => '05'
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Loading local JSON file
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Are you really allowed to access a local file?
– maasha
Nov 21 '12 at 19:21
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