ORA-1562 and ORA-1650 Unable to Extend Rollback Segment (Doc ID 1066542.6)

ORA-1562 and ORA-1650 Unable to Extend Rollback Segment (Doc ID 1066542.6)

APPLIES TO:

Oracle Database - Enterprise Edition - Version 8.0.3.0 and later
Oracle Solaris on SPARC (32-bit)

SYMPTOMS

You are working with the database that is using Rollback Segments (ie not using automatic undo) and you encounter ora-1562.

您正在使用回滚段的数据库（即未使用自动撤消），并且遇到了ora-1562

Error:    ORA 01562
Text:    "failed to extend rollback segment number %s"
------------------------------------------------------------------------
Cause:     Failure occurred when trying to extend rollback segment
Action:     This is normally followed by another error message that caused the failure.
                You may take the rollback segment offline to perform maintenance. 
                Use the alter rollback segment offline command to take the rollback segment offline.

The 0RA-1562 is often followed by another error which indicates the cause of the failure.

通常在0RA-1562后面跟随另一个错误，该错误指示失败的原因

For example, ORA-1650.

Error:      ORA 1650
Text:       unable to extend rollback segment <name> by <num> in tablespace <name>
-------------------------------------------------------------------------------
Cause:      Failed to allocate extent for the rollback segment in tablespace.
Action:     Use the ALTER TABLESPACE ADD DATAFILE statement to add one or more files to the specified tablespace.

CAUSE

Tablespace does not have sufficient contiguous space to allow for the extension of the rollback/Undo segment.

表空间没有足够的连续空间，无法扩展 rollback/Undo 段

The failure to extend error is raised when the next extent size is greater than the largest contiguous space.

当下一个扩展区大小大于最大连续空间时，将引发扩展错误失败

This error is only generated if, at the time the object tried to extend, there was not enough available contiguous space

仅当在尝试扩展对象时没有足够的可用连续空间时才会生成此错误

SOLUTION

Obtain the information necessary to address this issue.  获取解决此问题所需的信息

For the ORA-1650:

select max(bytes) from dba_free_space where tablespace_name = <tablespace name>;

The above query returns the largest available contiguous chunk of space. 上面的查询返回最大的可用连续块

Select next_extent, pct_increase from dba_rollback_segs where segment_name = <rollback segment name>;

The pct_increase is 0 by default.  默认情况下，pct_increase为0

There are several options for solving the failure to extend a rollback segment.

有几种方法可以解决无法扩展回滚段的问题

1. Ask users to commit their transactions to free space in the rollback segment

1. 要求用户将事务提交到回滚段中的可用空间

2. Manually coalesce adjacent free extents.  The extents must be adjacent for this to work.

2. 手动合并相邻的自由扩展区。这些范围必须相邻才能正常工作。

Alter tablespace <tablespace name> coalesce;

3. Add a datafile.

Alter tablespace <tablespace name> add datafile <full path and file name> size <integer> <K|M>;

4. Resize the datafile.

Alter database datafile <full path and file name> resize <integer> <K|M>;

In case of Manual Mode, "SET TRANSACTION USER ROLLBACK SEGMENT" may be attempted to force the use of a large rollback segment for a large transactions to try to overcome the ORA-1562.

在手动模式下，可以尝试使用 "SET TRANSACTION USER ROLLBACK SEGMENT" 来强制对大型事务使用较大的回滚段，以尝试克服ORA-1562。

User transactions are recorded in the rollback segment. The transaction remains open in the rollback segment until the user commits the changes.

用户事务记录在回滚段中。事务在回滚段中保持打开状态，直到用户提交更改为止。

If the user does not commit the changes, other users' transactions will eventually wrap around the rollback segment and "bump into" the open transaction.

如果用户不提交更改，则其他用户的事务最终将环绕回滚段并“弹出”未完成的事务。

At this point any new transactions will attempt to grab a new extent for the rollback segment.

在这一点上，任何新的事务都将尝试为回滚段获取新的范围。

If you tried using "set transaction use rollback segment" and received and unable to extend error, as a workaround take all other rollback segments offline.

如果您尝试使用 "set transaction use rollback segment" 并且收到了并且无法扩展错误，则作为一种解决方法，请使所有其他回滚段offline。

SET TRANSACTION USE ROLLBACK SEGMENT won't force DDL to use a particular rollback segment.

SET TRANSACTION USE ROLLBACK SEGMENT不会强制DDL使用特定的回滚段。

It's only effective on DML.

仅对DML有效

All DDL begins with an implicit COMMIT.

所有DDL都以隐式COMMIT开头

If you issue the SET TRANSACTION command, followed directly by DDL, the DDL will end the previous transaction as its first action.

如果您发出SET TRANSACTION命令，然后直接跟随DDL，则DDL将结束上一个事务作为其第一个操作

You cannot direct Oracle to use a specific rollback segment for DDL, only for DML.

您不能指示Oracle对DDL使用特定的回滚段，而仅对DML使用

REFERENCES

NOTE:1025288.6 - Troubleshooting Guide - 'Unable to Extend / Create' Errors