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What is the difference between v$mystat, v$sesstat and v$sysstat? I believe many inexperienced people don't know what to do about it. Therefore, this paper summarizes the causes and solutions of the problem. Through this article, I hope you can solve this problem.

The difference between v$mystat v$sesstat v$sysstat

My session stat current session Statistics-> mystat- > current session Statistics

Vsecretsesstats-> sesstat- > sessionstat are grouped by session

Vstatsysstats-> sysstat- > systemstat when the overall statistics of the system

V$statname

V$mystat refers to the stat of your own session.

V$sesstat is the stat of all session of the subsystem

In order to learn how to get the redo information generated by sql, you need to manipulate the view of vposts, mystatres, and vaststatname when you get the results from the query on the Internet:

1. Vaccounmystatrevaccounsesstat is used to count the session level and database statistics since the instance was started.

The structure of the two views is the same, but the statistics are not consistent.

Desc v$mystat

Is the name empty? Types

-

SID NUMBER

STATISTIC# NUMBER

VALUE NUMBER

SID represents the session number, corresponding to SID in v$session.

STATISTIC# represents statistical items

VALUE represents the value related to the statistical item

Only the session information of the current user will be found in the v$mystat view, and the v$sesstat will have all the session information within the entire instance. Therefore, the statistics of v&mystat are naturally included in v$sesstat.

SQL > desc v$sysstat

Name Null? Type

-

STATISTIC# NUMBER

NAME VARCHAR2 (64)

CLASS NUMBER

VALUE NUMBER

STAT_ID NUMBER

two。 In general, vaccounmystatjmsesstat is used in conjunction with v$statname.

UndefinedSQL > desc v$statname

Name Null? Type

-

STATISTIC# NUMBER

NAME VARCHAR2 (64)

CLASS NUMBER

STAT_ID NUMBER

The STATISTIC# in the v$statname view is associated with the STATISTIC# field in the vaccounsesstat. NAME is the corresponding English information, for example, to look up the redo information generated by a DML statement. You can write like this:

Select t.sid, t.value/1024/1024 size_m

From v$sesstat t, v$statname n

Where t.STATISTIC# = n.STATISTIC#

And name = 'redo size'

Order by 2

Select value

From v$mystat t, v$statname t1

Where t.STATISTIC# = t1.STATISTIC#

And t1.NAME = 'redo size'

The same is true for other information, just change the t1.name to the corresponding English name.

After reading the above, have you mastered the method of what is the difference between v$mystat, v$sesstat and v$sysstat? If you want to learn more skills or want to know more about it, you are welcome to follow the industry information channel, thank you for reading!

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