Declare @NameInxex Varchar(50)
select @NameInxex = name From sysindexes 
Where Name = 'IX_Local_Option'
if @NameInxex is null
set @NameInxex = ''

IF @NameInxex = ''
CREATE UNIQUE NONCLUSTERED INDEX IX_Local_Option 
    ON  Local_Option (Computer_Name)