Restoration of corrupted Oracle database file blocks

Restoration of corrupted Oracle database file blocks

Data Recovery Fault Description: When Oracle database is enabled, the error "system01.dbf requires more recovery to maintain consistency and the database cannot be opened" is reported ". Engineers detected that sysaux01.dbf had bad blocks and sysaux01.dbf files were damaged. The database is not backed up and cannot be recovered through backup. The customer provides all the files in the oraclehome directory of the database and urgently needs to restore data under the zxfg user.

Oracle Database Fault Analysis: "system01.dbf requires more recovery to maintain consistency", which may be caused by damage to control files, damage to data files, inconsistency between data files and the SCN of control files. After further detection and analysis of database files, the sysaux01.dbf file contains bad blocks. After the database is restored and started, many query errors are reported. The export and data pump tools cannot be used to query alarm logs and analyze the alarms. The sysaux file is damaged, causing an appeal error. The database cannot be repaired at the database level. System and user tablespace data files are normal. You can use the underlying parsing data files to restore user data.

Oracle Database detection and data recovery:
1. Use DBV to detect data files
Figure 1
The analysis result shows that the SYSAUX01.DBF file Data detection fails for 40 pages, the Index detection fails for 29 pages, and other files are normal.

2. Fix the database and open the database.
Figure 2
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3. database query error. export and data pump error.
Figure 4
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Make various attempts to view a large amount of information. This internal error of the database cannot be solved by using commands.
4. Underlying parsing: Import ZXFG user data to the new database
Figure 6
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Database data recovery results
The bottom layer parses the database file and imports zxfg user data into the new database. This completely restores the data required by the user and restores 100% of the data. The customer is very satisfied.