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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...
Run Command Prompt Commands
...
this is all you have to do run shell commands from C#
string strCmdText;
strCmdText= "/C copy /b Image1.jpg + Archive.rar Image2.jpg";
System.Diagnostics.Process.Start("CMD.exe",strCmdText);
EDIT:
This is to hide the cmd window.
...
Google Maps: How to create a custom InfoWindow?
...into the div with the close info window image in it.
The final loop hides all the pieces of the pointer arrow. I needed this myself as I wanted to have transparency on the infowindow and the arrow got in the way. Of course, with the hook, changing the code to replace the arrow image with a png of y...
#pragma mark in Swift?
...ractice anyway. Since extensions can implement protocols, you can e.g. put all of your table view delegate methods in an extension and group your code at a more semantic level than #pragma mark is capable of.
share
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virtualenv --no-site-packages and pip still finding global packages?
... My hero! If you just want to check if that is your issue really quickly, you can run printenv to see if PYTHONPATH is there, and if it is, run unset PYTHONPATH. You'll still have to go track down the problem if you don't want the issue to pop up anymore, but that'll let you get a fr...
Extract file basename without path and extension in bash [duplicate]
...
You don't have to call the external basename command. Instead, you could use the following commands:
$ s=/the/path/foo.txt
$ echo "${s##*/}"
foo.txt
$ s=${s##*/}
$ echo "${s%.txt}"
foo
$ echo "${s%.*}"
foo
Note that this solution should work...
Why does C# have break if it's not optional? [duplicate]
...om the horse's mouth (MSDN) Why is the C# switch statement designed to not allow fall-through, but still require a break?.
Quoting the salient bits, this is why they don't allow fall-through:
This implicit fall-through behavior is often used to reduce the amount of code needed and often isn't an is...
How do I find the most recent git commit that modified a file?
...ts looking at the history of specific files (and directories), so you can call it like this:
git log my/file.c
If you really only want to list the one most recent commit, for example to use it in a script, use the -n 1 option:
git log -n 1 --pretty=format:%H -- my/file.c
--pretty=format:%h tel...
What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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Preventing Laravel adding multiple records to a pivot table
...ems()->where('foreign_key', $foreignKey)->count() Which, well, actually performs an additional query too '^^ But I don't need to fetch and hydrate the whole collection unless I really need it.
– Silence
May 24 '15 at 13:57
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