23 Nov 2010 Due some reasons it performs an “INDEX SKIP SCAN” on index You can also easily hint complex queries by using the whole outline data of  2012年4月8日 不建议在代码中使用hint，在代码使用hint使得CBO无法根据实际的数据状态 NO_INDEX_FFS, Do not use fast full index scan (from Oracle 10g).

If more than one index is provided, the indexes are separated by at least one space; the INDEX_COMBINE hint is recommended for this use case though. ss. Oracle Tips by Burleson. Using CTAS with an Index Hint The CTAS with an index hint executes quite differently than CTAS with order by. 表明對表選擇索引的掃瞄方法. 例如: SELECT /*+INDEX(BSEMPMS SEX_INDEX) USE SEX_INDEX BECAUSE THERE ARE FEWMALE BSEMPMS */ FROM  For a hint on a combination of multiple indexes, Oracle recommends using INDEX_COMBINE rather than INDEX , because it is a more versatile hint. If the INDEX  11 Nov 2008 “If you want the optimizer to take the invisible index into account, you must use the index hint, as shown in the following example:“. Oracle  28 Oct 2013 Here is a complete list of Hints use for the DBA Oracle; Hint for access by FTS, index scan, ordered, by RoWID

If you force the use of the index with an hint, Oracle will do a full index scan. It will not be interesting for you.If your query has a sense, maybe your data model is not appropriate. Maybe a good way is to split you column nr_certificate in two columns. If it's possible, it will be easy to you after to have the good and quick query.

There is an appropriate index on column_having_index, and its use actually increase performance, but Oracle didn't use it You should gather statistics on your table to let optimizer see that index access can help. Using direct hint is not a good practice. The easiest way to force index usage is with the index hint. When forcing an index, always use the table alias whenever you have a query that specifies an alias. For example, the following query will force the use of the dept_idx index because the emp table is aliased with "e": select /*+ index(e,dept_idx) */ * from emp e; You can use the INDEX hint for domain, B-tree, bitmap, and bitmap join indexes. However, Oracle recommends using INDEX_COMBINE rather than INDEX for the combination of multiple indexes, because it is a more versatile hint. index_hint::= Text description of the illustration index_hint.gif Use of the USE_NL and USE_MERGE hints is recommended with the ORDERED hint. Oracle uses these hints when the referenced table is forced to be the inner table of a join; the hints are ignored if the referenced table is the outer table.

2019年9月9日 表明對錶選擇索引的掃描方法. 例如: SELECT /*+INDEX(BSEMPMS SEX_INDEX) USE SEX_INDEX BECAUSE THERE ARE FEWMALE 

表明對表選擇索引的掃瞄方法. 例如: SELECT /*+INDEX(BSEMPMS SEX_INDEX) USE SEX_INDEX BECAUSE THERE ARE FEWMALE BSEMPMS */ FROM  For a hint on a combination of multiple indexes, Oracle recommends using INDEX_COMBINE rather than INDEX , because it is a more versatile hint. If the INDEX  11 Nov 2008 “If you want the optimizer to take the invisible index into account, you must use the index hint, as shown in the following example:“. Oracle  28 Oct 2013 Here is a complete list of Hints use for the DBA Oracle; Hint for access by FTS, index scan, ordered, by RoWID 23 Nov 2010 Due some reasons it performs an “INDEX SKIP SCAN” on index You can also easily hint complex queries by using the whole outline data of  2012年4月8日 不建议在代码中使用hint，在代码使用hint使得CBO无法根据实际的数据状态 NO_INDEX_FFS, Do not use fast full index scan (from Oracle 10g).

Using INDEX Hints. When you specify an INDEX Hint, the optimizer knows that it has to use the INDEX specified in the hint. In this case, the optimizer does not go for a Full Table Scan nor does it use any other index. In addition, it does not calculate the cost of the Index to be used.

Index hints can also be placed inside subqueries. Oracle provides the index hint, the and_equal hint, the index_asc hint, the index_combine hint, the index_desc hint, and the index_ffs hint to redirect the optimizer's use of indexes to access table rows. Let’s begin our discussion with the most common hint, the index hint. The Index Hint

select /*+ index(customer cust_primary_key_idx) */ * from customer; Also note that of you alias the table, you must use the alias in the index hint: select /*+ 

For a hint on a combination of multiple indexes, Oracle recommends using INDEX_COMBINE rather than INDEX , because it is a more versatile hint. If the INDEX  11 Nov 2008 “If you want the optimizer to take the invisible index into account, you must use the index hint, as shown in the following example:“. Oracle  28 Oct 2013 Here is a complete list of Hints use for the DBA Oracle; Hint for access by FTS, index scan, ordered, by RoWID 23 Nov 2010 Due some reasons it performs an “INDEX SKIP SCAN” on index You can also easily hint complex queries by using the whole outline data of  2012年4月8日 不建议在代码中使用hint，在代码使用hint使得CBO无法根据实际的数据状态 NO_INDEX_FFS, Do not use fast full index scan (from Oracle 10g).

2011年9月6日 在SQL語句優化過程中，我們經常會用到hint,現總結一下在SQL優化過程中常見 Oracle hint的用法： 如果是要指定使用某個Index,則利用規則。 1. You can use the INDEX hint for domain, B-tree, bitmap, and bitmap join indexes. However, Oracle recommends using INDEX_COMBINE rather than INDEX for the   The index hint is the key here, but the more up to date way of specifying it is with the column naming method rather than the index naming method