awr:
1. 定期對 DLog 相關的索引執行 coalesce 操作 而非 rebuild 操作。 rebuild 可能導致索引高度下降,當再有 大量插入後可能會導致索引root node split
2. 分區表的話,考慮使用global hash index ,global hash index可以很大程度上避免索引插入爭用。
SQL> analyze index business.PK_TINSURED validate structure;
Index analyzed.
SQL> select blocks,lf_blks,del_lf_rows from index_stats;
BLOCKS LF_BLKS DEL_LF_ROWS
---------- ---------- -----------
219608 213822 334
SQL> alter index business.PK_TINSURED coalesce;
Index altered.
Elapsed: 00:01:56.97
SQL> analyze index business.PK_TINSURED validate structure;
Index analyzed.
Elapsed: 00:00:27.93
SQL> select blocks,lf_blks,del_lf_rows from index_stats;
BLOCKS LF_BLKS DEL_LF_ROWS
---------- ---------- -----------
219608 165849 0