• 欢迎访问搞代码网站,推荐使用最新版火狐浏览器和Chrome浏览器访问本网站!
  • 如果您觉得本站非常有看点,那么赶紧使用Ctrl+D 收藏搞代码吧

来自AskTom的关于Soft Parse的解释_sqlserver

sqlserver 搞代码 7年前 (2018-06-16) 147次浏览 已收录 0个评论

There are two types of parses (well, actually “three” these days).

They are

o HARD parse — the query has never been seen before, isn’t in the shared pool. 

http://www.gaodaima.com/35000.html来自AskTom的关于Soft Parse的解释_sqlserver

We must parse it, hash it, look in the shared pool for it, don’t find it,
security check it, optimize it, etc (lots of work).

o SOFT parse — the query has been seen before, is in the shared poo.  We have
to parse it, hash it, look in the shared pool for it and find it (less work then
a hard parse but work none the less)

o a kinder, softer SOFT parse — you are using session_cached_cursors (search
this site for that word for info).  We take your query, look in the sessions
cursor cache — find the cursor and reuse it.  Very very little work.

So, after “startup”, you go into sqlplus and do this:

SQL> alter session set session_cached_cursors=0; — just making sure this is off
SQL> select * from emp;  — hard parse
SQL> select * from emp; — soft parse
SQL> select * from emp; — soft parse
SQL> alter session set session_cached_cursors=100; — enable this feature
SQL> select * from emp;  — soft parse
SQL> select * from emp; — kinder, gentler, soft parse

link:

http://asktom.oracle.com/pls/ask/f?p=4950:8:::::F4950_P8_DISPLAYID:801662252143

 

欢迎大家阅读《来自AskTom的关于Soft Parse的解释_sqlserver,跪求各位点评,若觉得好的话请收藏本文,by 搞代码


搞代码网(gaodaima.com)提供的所有资源部分来自互联网,如果有侵犯您的版权或其他权益,请说明详细缘由并提供版权或权益证明然后发送到邮箱[email protected],我们会在看到邮件的第一时间内为您处理,或直接联系QQ:872152909。本网站采用BY-NC-SA协议进行授权
转载请注明原文链接:来自AskTom的关于Soft Parse的解释_sqlserver

喜欢 (0)
[搞代码]
分享 (0)
发表我的评论
取消评论

表情 贴图 加粗 删除线 居中 斜体 签到

Hi,您需要填写昵称和邮箱!

  • 昵称 (必填)
  • 邮箱 (必填)
  • 网址