停止空想

ops$tkyte@ORA920> select * from t where object_id = 55;

Execution Plan

———————————————————-

   0      SELECT STATEMENT Optimizer=CHOOSE (Cost=3 Card=13 Bytes=96)

   1    0   TABLE ACCESS (BY INDEX ROWID) OF ‘T’ (Cost=3 Card=13 Bytes=96)

   2    1     INDEX (RANGE SCAN) OF ‘T_IDX’ (NON-UNIQUE) (Cost=13 Card=1)

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