|* 3 | INDEX RANGE SCAN | INDEX_T1 | 1 | 17 | 0 (0)| 00:00:01
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Predicate Information (identified by operation id):
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3 - access("A"."TABLE_NAME"="B"."TABLE_NAME")
Note
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- dynamic sampling used for this statement (level=2)
统计信息
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4 recursive calls
0 db block gets
23 consistent gets
0 physical reads
0 redo size
807 bytes sent via SQL*Net to client
415 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
8 rows processed
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假定我们利用提示改变的表的连接顺序
ORACLE的解析器按照从右到左的顺序处理FROM子句中的表名，FROM子句中写在最后的表(基础表 driving table)将被最先处理，在FROM子句中包含多个表的情况下,你必须选择记录条数最少的表作为基础表。如果有3个以上的表连接查询, 那就需要选择交叉表(intersection table)作为基础表, 交叉表是指那个被其他表所引用的表.