1. For ORA-1578:
There are two ways in which we can extract the data from a corrupted table:
a) Using DBMS_REPAIR.SKIP_CORRUPT_BLOCKS
b) Using Event 10231
a) Connect as sysdba user:
execute DBMS_REPAIR.SKIP_CORRUPT_BLOCKS(‘<schema_name>’,'<table_name>’);
Put the schema name and the table name of the corrupted table.
Then issue the following command to craete a new table from corrupted table:
create table new_table as select * from corrupted_table_name;
Now Drop the corrupted table, rename the newly created table to its original name and
clear the attribute for the new table as:
execute DBMS_REPAIR.SKIP_CORRUPT_BLOCKS
(‘<schema_name>’,'<table_name>’,flags=>dbms_repair.noskip_flag);
b) Set the event 10231 at session level to skip corrupted rows:
ALTER SESSION SET EVENTS ’10231 TRACE NAME CONTEXT FOREVER, LEVEL 10′;
Then issue the following command to craete a new table from corrupted table:
create table new_table as select * from corrupted_table_name;
Now Drop the corrupted table, rename the newly created table to its original name.
2. For ORA-8103
This is a case of LOGICAL CORRUPTION and cannot be taken care by skipping the corrupted rows.
Follow Metalink Note 422547.1 to salvage data in case of ORA-8103
