Use the alter system check datafiles command, alterdatafiles

Use the alter system check datafiles command, alterdatafiles

The alter system check datafiles command seems to have been seen in the White Paper, so I searched for it in the SQL reference in the official document. The description of this statement is as follows:

check_datafiles_clause In a distributed database system, such as a Real Application Clusters environment, this clause updates an instance's SGA from the database control file to reflect information on all online datafiles.•Specify GLOBAL to perform this synchronization for all instances that have opened the database. This is the default.•Specify LOCAL to perform this synchronization only for the local instance.Your instance should have the database open.

This command is generally used in the rac environment. For example, one node cannot access a datafile (only this node is inaccessible, and other nodes can access it ), on this node that cannot be accessed, you can use the alter system check datafiles command to update the sga information of the Instance. The source of the update information is the control file.

Then, search for the keyword 'alter system check datafile' in mos and find the following knowledge points:

Alter system check datafiles does not check read-only files .--- Master Note: Overview of Oracle Tablespace Management (Document ID 1493350.1) The following articles also have some learning values: Alter system check datafiles does not work as expected (Document ID 1071756.6)