为什么此Cursor的输出为null? [英] Why is the Output of this Cursor null?

问题描述

id列包含值
1
2
3
---------------
以下语句的输出为"hello"，这意味着@i为空.有人可以向我解释这怎么可能吗?

The id column contain the value
1
2
3
---------------
The output of the following statement is "hello", which would mean that @i was null. Can anybody explain to me how this can be?

declare c cursor for select id from student1 
open c 
declare @i int 
fetch next from c into @i 

if @i!=null 
print @i 
else 
print 'hello'

任何帮助深表感谢！

在此先感谢！

Any help is deeply appreciated!

Thanks in advance!

推荐答案

try:

try :

if @i is not null
print @i
else
print 'hello'

这给出的输出为1

this gives the output as 1

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