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postgresql return 0 if returned value is null
...ns the first of its arguments that is not null.
Null is returned only if all arguments are null. It is often
used to substitute a default value for null values when data is
retrieved for display.
Edit
Here's an example of COALESCE with your query:
SELECT AVG( price )
FROM(
SELECT *, cum...
How to move a git repository into another directory and make that directory a git repository?
...create it)
$ cp -r gitrepo1 newrepo
# remove .git from old repo to delete all history and anything git from it
$ rm -rf gitrepo1/.git
Note that the copy is quite expensive if the repository is large and with a long history. You can avoid it easily too:
# move the directory instead
$ mv gitrepo1 ...
Remove all spaces from a string in SQL Server
What is the best way to remove all spaces from a string in SQL Server 2008?
23 Answers
...
How to remove line breaks (no characters!) from the string?
...
You should be able to replace it with a preg that removes all newlines and carriage returns. The code is:
preg_replace( "/\r|\n/", "", $yourString );
Even though the \n characters are not appearing, if you are getting carriage returns there is an invisible character there. The pr...
All possible array initialization syntaxes
What are all the array initialization syntaxes that are possible with C#?
16 Answers
1...
How to pull request a wiki page on GitHub?
...control, as for source code:
My proposed workflow is this:
Manually create a fork of the Taffy wiki on your Github account:
Create a new repository on your github account. Let's call it "Taffy-Wiki".
Clone the Taffy wiki repo to your local machine somewhere: git clone git@githu...
Json.net serialize/deserialize derived types?
...Derived). This way, it doesn't bloat your JSON as much as TypeNameHandling.All.
– AJ Richardson
Mar 25 '15 at 13:18
I ...
Why not use always android:configChanges=“keyboardHidden|orientation”?
...andle this myself. Yes, I know what I'm doing"
Is this a good thing? We shall soon see...
No worries?
One of the pros you start with is that there is:
no need to worry about your activity been rotated
In many cases, people mistakenly believe that when they have an error that is being genera...
Why is '+' not understood by Python sets?
...t int/long) define this operation across a sequence of boolean values and call it "bitwise or". In fact this operation is so similar to the set union that binary integers are sometimes also called "Bit sets", where the elements in the set are taken to be the natural numbers.
Because int already de...
Is there a way to get rid of accents and convert a whole string to regular letters?
...f accents and making those letters regular apart from using String.replaceAll() method and replacing letters one by one?
Example:
...