Can You Delete $ORACLE_HOME/.patch_storage Directory ? (文档 ID 403218.1)

今天给自己虚拟机打最新的11.2.0.4.6的GI/DB的PSU补丁，碰到坑了，之前虚拟机空间不足，我把.patch_storage给清了，结果就打补丁报错，特此纪念下！

In this Document

 Goal Solution References

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APPLIES TO:

Oracle Database - Enterprise Edition - Version 9.2.0.1 to 12.1.0.1 [Release 9.2 to 12.1]
Information in this document applies to any platform.

GOAL

Is it necessary to keep the $ORACLE_HOME/.patch_storage directory after successful installation of a patch?

SOLUTION

Yes, It is necessary to keep the $ORACLE_HOME/.patch_storage directory even after successful installation of a patch. 

1) When you apply an interim patch to an Oracle home, OPatch stores the patch information in $ORACLE_HOME/.patch_storage directory. Inside this directory, there are separate directories created for each patch applied to the Oracle home. Interim patches are bug fixes that are made available to customers in response to specific bugs. Critical Patch Update (CPU) and Patch Set Updates (PSUs)  is also a kind of patche. The latest CPU/PSU will rollback the previously applied CPU/PSU as CPU/PSU is cumulative. So this rollback information is from the .patch_storage directory. 


2) You may come across a bug conflict and might want to remove the conflicting patch. This process is known as patch rollback. During patch installation, OPatch saves copies of all the files that were replaced by the new patch before the new versions of these files are loaded and stores it in $ORACLE_HOME/.patch_storage/patch ID/. These saved files are called rollback files and are the key to making patch rollback possible. 

3) Every time you apply a patch, you make changes to your inventory. Sometimes that change may corrupt the inventory. From Oracle RDBMS 10.2.0.X.X onwards when you apply a patch, OPatch creates a snapshot of your inventory and stores it in $ORACLE_HOME/.patch_storage/<patch-id_timestamp> directory. The $ORACLE_HOME/.patch_storage/<patch-id_timestamp>/restore.sh script that comes with OPatch to remove any changes that were made to the inventory after the application of the patch. 

More over the .patch_storage directory is made hidden also adds to the fact that it should not be deleted. Note 550522.1 can be followed to perform maintenance operation on this directory.