在空表中执行缓慢的查询。 (删除大量插入后) [英] Slow query execution in an empty table. (after deleting a large amount of inserts)
问题描述
我在oracle数据库中有一个包含15个字段的表。
此表有350万个插入。我将它们全部删除。
从表
$中删除
p $ p>
之后,每当我执行select语句时,
即使表为空,我的响应也会很慢(7秒)。
只有在我根据索引字段搜索
的情况下才能获得正常响应。
为什么?
解决方案正如Gritem所说,你需要了解高水位等。
如果你不想要现在要
截断
表(因为已插入新数据),使用alter table xyz shrink space
记录这里 10gI have a table in an oracle database with 15 fields. This table had 3500000 inserts. I deleted them all.
delete from table
After that, whenever I execute a select statement
I get a very slow response (7 sec) even though the table is empty. I get a normal response only in the case that I search according to an indexed field.Why?
解决方案As Gritem says, you need to understand high water marks etc
If you do not want to
truncate
the table now (because fresh data has been inserted), usealter table xyz shrink space
documented here for 10g这篇关于在空表中执行缓慢的查询。 (删除大量插入后)的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!