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SQL Server insert if not exists best practice
...sert Competitors where doesn't already exist":
INSERT Competitors (cName)
SELECT DISTINCT Name
FROM CompResults cr
WHERE
NOT EXISTS (SELECT * FROM Competitors c
WHERE cr.Name = c.cName)
share
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...
What's the false operator in C# good for?
...he operator false declared in T, and T.&(x, y) is an invocation of the selected operator &. In other words, x is first evaluated and operator false is invoked on the result to determine if x is definitely false. Then, if x is definitely false, the result of the operation is the value previou...
Convert varchar to uniqueidentifier in SQL Server
...
DECLARE @uuid VARCHAR(50)
SET @uuid = 'a89b1acd95016ae6b9c8aabb07da2010'
SELECT CAST(
SUBSTRING(@uuid, 1, 8) + '-' + SUBSTRING(@uuid, 9, 4) + '-' + SUBSTRING(@uuid, 13, 4) + '-' +
SUBSTRING(@uuid, 17, 4) + '-' + SUBSTRING(@uuid, 21, 12)
AS UNIQUEIDENTIFIER)
...
How do I temporarily disable triggers in PostgreSQL?
...ct = 'disable';
else
act = 'enable';
end if;
for r in select c.relname from pg_namespace n
join pg_class c on c.relnamespace = n.oid and c.relhastriggers = true
where n.nspname = nsp
loop
execute format('alter table %I %s trigger all', r.relname, act)...
How to do an INNER JOIN on multiple columns
...n once by giving the joined tables an alias, as in the following example:
SELECT
airline, flt_no, fairport, tairport, depart, arrive, fare
FROM
flights
INNER JOIN
airports from_port ON (from_port.code = flights.fairport)
INNER JOIN
airports to_port ON (to_port.code = flights.tair...
How to copy text from Emacs to another application on Linux
...Emacs paste and Emacs copy work with system paste, you need to add (setq x-select-enable-clipboard t) to your .emacs. Or try
META-X set-variable RET x-select-enable-clipboard RET t
I think this is pretty standard modern Unix behavior.
It's also important to note (though you say you're using Em...
Xcode - How to fix 'NSUnknownKeyException', reason: … this class is not key value coding-compliant f
...ng from "File's Owner" under "Place Holders" to "view" under "Objects" and selecting the view outlet.
– Nirma
Aug 11 '11 at 14:49
...
How do I get my solution in Visual Studio back online in TFS?
...t-click on the solution name right at the top of the Solution Explorer and select the Go Online option. Clicking this allowed me to select the files that had been changed when I was offline and make the solution online again.
After finding the solution, I found the following msdn forum thread which...
Max return value if empty query
...oeSize = Workers.Where(x => x.CompanyId == 8)
.Select(x => x.ShoeSize)
.DefaultIfEmpty(0)
.Max();
The zero in DefaultIfEmpty is not necessary.
...
How to check if an option is selected?
...
UPDATE
A more direct jQuery method to the option selected would be:
var selected_option = $('#mySelectBox option:selected');
Answering the question .is(':selected') is what you are looking for:
$('#mySelectBox option').each(function() {
if($(this).is(':selected')) ....