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How do I get SUM function in MySQL to return '0' if no values are found?
...
Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
To see it in action, please see this sql fiddle: http://www.sqlfiddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nul...
Select all elements with “data-” attribute without using jQuery
Using only JavaScript, what is the most efficient way to select all DOM elements that have a certain data- attribute (let's say data-foo ). The elements may be different tag elements.
...
symbol(s) not found for architecture i386
....
To add frameworks, right click on the project name in the project view, select Add, then select Existing frameworks... from the list. Then find the framework with the symbols you're missing.
As to how you find which frameworks you need, I've found using google the easiest, though you could proba...
How to fix .pch file missing on build?
...the bottom of the drop-down menu.
At the top left of the Properties Pages,
select All Configurations from the drop-down menu.
Open the C/C++ tree and select Precompiled Headers
Precompiled Header: Select Use (/Yu)
Fill in the Precompiled Header File field. Standard is stdafx.h
Click Okay
If you do n...
SQL Server query to find all permissions/access for all users in a database
...s the user/role has on an object. Examples could include CONNECT, EXECUTE, SELECT
DELETE, INSERT, ALTER, CONTROL, TAKE OWNERSHIP, VIEW DEFINITION, etc.
This value may not be populated for all roles. Some built in roles have implicit permission
d...
Solutions for INSERT OR UPDATE on SQL Server
...nd PK violations you can use something like this:
begin tran
if exists (select * from table with (updlock,serializable) where key = @key)
begin
update table set ...
where key = @key
end
else
begin
insert into table (key, ...)
values (@key, ...)
end
commit tran
or
begin tran
upda...
Return 0 if field is null in MySQL
...
Would that be IFNULL((SELECT SUM(uop.price * uop.qty) FROM uc_order_products uop WHERE uo.order_id = uop.order_id) AS products_subtotal, 0)?
– Kevin
Oct 22 '10 at 13:46
...
The import javax.servlet can't be resolved [duplicate]
...ibraries tab
Click Add External JARs...
Browse to find servlet-api.jar and select it.
Click OK to update the build path.
Or, if you copy the JAR into your project:
Right-click the project, click Properties.
Choose Java Build Path.
Click Add JARs...
Find servlet-api.jar in your project and select...
What is the difference between a stored procedure and a view?
...iece of SQL, I would define a view like:
CREATE VIEW vw_user_profile
AS
SELECT A.user_id, B.profile_description
FROM tbl_user A LEFT JOIN tbl_profile B ON A.user_id = b.user_id
GO
Thus, if I want to query profile_description by user_id in the future, all I have to do is:
SELECT profile_descr...
Why can't radio buttons be “readonly”?
...ton by disabling only the un-checked radio buttons. It keeps the user from selecting a different value, and the checked value will always post on submit.
Using jQuery to make readonly:
$(':radio:not(:checked)').attr('disabled', true);
This approach also worked for making a select list readonly, ...