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pubs2의 titles라는 테이블에 nonclustered index를 생성

create nonclustered index idx_1 on titles(advance)

** index forward scan

select * from titles (index idx_1)

query plan]

STEP 1
       The type of query is SELECT.

       FROM TABLE
           titles
       Nested iteration.
       Index : idx_1
       Forward scan.
       Positioning at index start.

** index backward scan

select * from titles (index idx_1) order by advance desc

query plan]

STEP 1
       The type of query is SELECT.

       FROM TABLE
           titles
       Nested iteration.
       Index : idx_1
       Backward scan.
       Positioning at index end.