Question 7: Can you tell me what the difference of two SQL statements at
performance of execution?
Statement 1:
if NOT EXISTS (select * from publishers where state = 'NY')
begin
SELECT 'Sales force needs to penetrate New York market'end
else
begin
SELECT 'We have publishers in New York'
end
Statement 2:
if EXISTS (select * from publishers where state = 'NY')
begin
SELECT 'We have publishers in New York'
end
else
begin
SELECT 'Sales force needs to penetrate New York market'
end
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