1.플랜을 보고 해결방안을 작성하시오.(인덱스 생성, 테이블 변경 등등)

1-1.
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| Id  | Operation         | Name     | Starts | A-Rows |   A-Time   | Buffers |
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|   0 | SELECT STATEMENT  |          |      1 |     10 |00:00:00.01 |    100K |
|*  1 |  TABLE ACCESS FULL| T_CUST74 |      1 |     10 |00:00:00.01 |    100K |
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1-2.
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| Id  | Operation                           | Name           | Starts | A-Rows |   A-Time   | Buffers |
-------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                    |                |      1 |   1000 |00:00:00.01 |   15000 |
|*  1 |  TABLE ACCESS BY INDEX ROWID BATCHED| T_CUST74       |      1 |   1000 |00:00:00.01 |   15000 |
|*  2 |   INDEX RANGE SCAN                  | IX_T_CUST74_01 |      1 |  10000 |00:00:00.01 |     500 |
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1-3.
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| Id  | Operation                           | Name            | Starts | A-Rows |   A-Time   | Buffers |
--------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                    |                 |      1 |     10 |00:00:00.01 |    1010 |
|   1 |  TABLE ACCESS BY INDEX ROWID BATCHED| T_ORDER74       |      1 |     10 |00:00:00.01 |    1010 |
|*  2 |   INDEX RANGE SCAN                  | IX_T_ORDER74_02 |      1 |     10 |00:00:00.01 |    1000 |
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1-4.
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| Id  | Operation                           | Name           | Starts | A-Rows |   A-Time   | Buffers |
-------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                    |                |      1 |   1000 |00:00:00.01 |    1000 |
|   1 |  TABLE ACCESS BY INDEX ROWID BATCHED| T_CUST74       |      1 |   1000 |00:00:00.01 |    1000 |
|*  2 |   INDEX RANGE SCAN                  | IX_T_CUST74_01 |      1 |   1000 |00:00:00.01 |      10 |
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1-5.

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| Id  | Operation                                   | Name             | Starts | A-Rows |   A-Time   | Buffers | Reads  |
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|   0 | SELECT STATEMENT                            |                  |      1 |  10000 |00:00:00.12 |    1772 |     32 |
|*  1 |  COUNT STOPKEY                              |                  |      1 |  10000 |00:00:00.12 |    1772 |     32 |
|   2 |   PARTITION RANGE ALL                       |                  |      1 |  10000 |00:00:00.10 |    1772 |     32 |
|   3 |    TABLE ACCESS BY LOCAL INDEX ROWID BATCHED| T_ORDER61        |      1 |  10000 |00:00:00.08 |    1772 |     32 |
|*  4 |     INDEX RANGE SCAN                        | IX_T_ORDER_61_02 |      1 |  10000 |00:00:00.02 |     688 |      1 |
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https://cafe.naver.com/dbstudydapsqlp

https://cafe.naver.com/sqlpd/71143