优化前，执行计划走了nl，1个多小时查不出结果
第二次优化后，首次00:00:10.21出结果，重复执行（有缓存）的情况下3s出结果。
统计信息不准导致执行计划出错跑不出结果，优化后只要1分钟(三)
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| 0 | SELECT STATEMENT | | 1 | 1065 | 6 (34)| 00:00:01 | | | |
| 1 | PX COORDINATOR | | | | | | | | |
| 2 | PX SEND QC (RANDOM) | :TQ10004 | 1 | 1065 | 6 (34)| 00:00:01 | Q1,04 | P->S | QC (RAND) |
| 3 | SORT GROUP BY | | 1 | 1065 | 6 (34)| 00:00:01 | Q1,04 | PCWP | |
| 4 | PX RECEIVE | | 1 | 1065 | 6 (34)| 00:00:01 | Q1,04 | PCWP | |
| 5 | PX SEND HASH | :TQ10003 | 1 | 1065 | 6 (34)| 00:00:01 | Q1,03 | P->P | HASH |
| 6 | SORT GROUP BY | | 1 | 1065 | 6 (34)| 00:00:01 | Q1,03 | PCWP | |
| 7 | PX RECEIVE | | 1 | 1065 | 6 (34)| 00:00:01 | Q1,03 | PCWP | |
| 8 | PX SEND HASH | :TQ10002 | 1 | 1065 | 6 (34)| 00:00:01 | Q1,02 | P->P | HASH |
| 9 | SORT GROUP BY | | 1 | 1065 | 6 (34)| 00:00:01 | Q1,02 | PCWP | |
|* 10 | HASH JOIN RIGHT OUTER| | 1 | 1065 | 5 (20)| 00:00:01 | Q1,02 | PCWP | |
| 11 | PX RECEIVE | | 1 | 526 | 2 (0)| 00:00:01 | Q1,02 | PCWP | |
| 12 | PX SEND HASH | :TQ10000 | 1 | 526 | 2 (0)| 00:00:01 | Q1,00 | P->P | HASH |
| 13 | PX BLOCK ITERATOR | | 1 | 526 | 2 (0)| 00:00:01 | Q1,00 | PCWC | |
| 14 | TABLE ACCESS FULL| BBB | 1 | 526 | 2 (0)| 00:00:01 | Q1,00 | PCWP | |
| 15 | PX RECEIVE | | 1 | 539 | 2 (0)| 00:00:01 | Q1,02 | PCWP | |
| 16 | PX SEND HASH | :TQ10001 | 1 | 539 | 2 (0)| 00:00:01 | Q1,01 | P->P | HASH |
| 17 | PX BLOCK ITERATOR | | 1 | 539 | 2 (0)| 00:00:01 | Q1,01 | PCWC | |
| 18 | TABLE ACCESS FULL| AAA | 1 | 539 | 2 (0)| 00:00:01 | Q1,01 | PCWP | |
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Predicate Information (identified by operation id):
---------------------------------------------------
10 - access("A1"."RES_ID"(+)="A2"."RES_CODE")
Statistics
----------------------------------------------------------
585 recursive calls
4 db block gets
14267 consistent gets
13126 physical reads
808 redo size
4888 bytes sent via SQL*Net to client
840 bytes received via SQL*Net from client
6 SQL*Net roundtrips to/from client
23 sorts (memory)
0 sorts (disk)
63 rows processed
优化前，执行计划走了nl，1个多小时查不出结果
第一次优化后，首次00:00:47.64可以出结果
第二次优化后，首次00:00:10.21出结果，重复执行（有缓存）的情况下3s出结果。
优化前，执行计划走了nl，1个多小时查不出结果
第二次优化后，首次00:00:10.21出结果，重复执行（有缓存）的情况下3s出结果。