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SQL - HAVING vs. WHERE
...nce HAVING works correctly.
As a rule of thumb, use WHERE before GROUP BY and HAVING after GROUP BY. It is a rather primitive rule, but it is useful in more than 90% of the cases.
While you're at it, you may want to re-write your query using ANSI version of the join:
SELECT L.LectID, Fname, Lnam...
How to see the CREATE VIEW code for a view in PostgreSQL?
...an easy way to see the code used to create a view using the PostgreSQL command-line client?
6 Answers
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Why is it string.join(list) instead of list.join(string)?
...e any iterable can be joined (e.g, list, tuple, dict, set), but the result and the "joiner" must be strings.
For example:
'_'.join(['welcome', 'to', 'stack', 'overflow'])
'_'.join(('welcome', 'to', 'stack', 'overflow'))
'welcome_to_stack_overflow'
Using something else than strings will raise t...
How to insert a line break before an element using CSS
... block; }
This will have the effect of ensuring a line break both before and after the element.
There is not a way to have CSS insert something that acts like a line break only before an element and not after. You could perhaps cause a line-break before as a side-effect of other changes, for exam...
How Can I Set the Default Value of a Timestamp Column to the Current Timestamp with Laravel Migratio
...r/Migrations. I have gone through the Laravel documentation several times, and I don't see how I can make that the default for a timestamp column.
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jQuery .on('change', function() {} not triggering for dynamically created inputs
The problem is that I have some dynamically created sets of input tags and I also have a function that is meant to trigger any time an input value is changed.
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How to pass a variable from Activity to Fragment, and pass it back?
I am currently making an android app, and I want to pass a date between activity and fragment.
My activity has a button, which opens the fragment: DatePickerFragment.
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How to find a hash key containing a matching value
... be an array of all the matching values, where each is an array of the key and value.
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Extract file name from path, no matter what the os/path format
...ers suggest won't work in all cases: if you're running the script on Linux and attempt to process a classic windows-style path, it will fail.
Windows paths can use either backslash or forward slash as path separator. Therefore, the ntpath module (which is equivalent to os.path when running on windo...
How does JPA orphanRemoval=true differ from the ON DELETE CASCADE DML clause
...ollection of Items that belong to an Invoice object (in memory operation), and then "save" the Invoice, the removed Item should be deleted from the underlying DB.
– garyKeorkunian
Oct 16 '12 at 15:38
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