declare @str nvarchar(100)
set @str ='aa.cc,'
select @st= substring(@st,7,10)
if(@st !='')
print '不爲空'
else
print '爲空'
declare @str nvarchar(100)
set @str ='aa.cc,'
select @st= substring(@st,7,10)
if(@st !='')
print '不爲空'
else
print '爲空'