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Is it good practice to NULL a pointer after deleting it?
... against setting pointers to 0 after delete would be that doing so just masks double delete bugs and leaves them unhandled.
It's best to not have double delete bugs, obviously, but depending on ownership semantics and object lifecycles, this can be hard to achieve in practice. I prefer a masked dou...
How to list only the file names that changed between two commits?
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PeterPeter
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Check if a row exists, otherwise insert
...I assume a single row for each flight? If so:
IF EXISTS (SELECT * FROM Bookings WHERE FLightID = @Id)
BEGIN
--UPDATE HERE
END
ELSE
BEGIN
-- INSERT HERE
END
I assume what I said, as your way of doing things can overbook a flight, as it will insert a new row when there are 10 tickets max and...
Sorting a tab delimited file
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Using bash, this will do the trick:
$ sort -t$'\t' -k3 -nr file.txt
Notice the dollar sign in front of the single-quoted string. You can read about
it in the ANSI-C Quoting sections of the bash man page.
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Google Maps v3 - limit viewable area and zoom level
...nd event, and if the map is dragged outside the allowed bounds, move it back inside. You can define your allowed bounds in a LatLngBounds object and then use the contains() method to check if the new lat/lng center is within the bounds.
You can also limit the zoom level very easily.
Consider the f...
jQuery: checking if the value of a field is null (empty)
Is this a good way to check if the value of a field is null ?
7 Answers
7
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Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
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Guesswork (even educated guesswork) is fun but you really need to go to the standards documents to be sure. For example, ISO C11 states (my emphasis):
If the value of argc is greater than zero, the string pointed to by argv[0] re...
How to parse float with two decimal places in javascript?
I have the following code. I would like to have it such that if price_result equals an integer, let's say 10, then I would like to add two decimal places. So 10 would be 10.00.
Or if it equals 10.6 would be 10.60. Not sure how to do this.
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How to use double or single brackets, parentheses, curly braces
I am confused by the usage of brackets, parentheses, curly braces in Bash, as well as the difference between their double or single forms. Is there a clear explanation?
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Clearing all cookies with JavaScript
How do you delete all the cookies for the current domain using JavaScript?
18 Answers
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