B-tree Index Faults ​

Symptom ​

The following error message is displayed, indicating that the index is lost occasionally.

ERROR: index 'xxxx_index' contains unexpected zero page
Or
ERROR: index 'pg_xxxx_index' contains unexpected zero page
Or
ERROR: compressed data is corrupt

Cause Analysis ​

This type of error is caused by the index fault. The possible causes are as follows:

• The index is unavailable due to software bugs or hardware faults.
• The index contains many empty pages or almost empty pages.
• During concurrent DDL execution, the network is intermittently disconnected.
• The index failed to be created when indexes are concurrently created.
• A network fault occurs when a DDL or DML operation is performed.

Procedure ​

Run the REINDEX command to rebuild the index.

1. Log in to the host as the OS user omm.

2. Run the following command to connect to the database:

   gsql -d postgres -p 8000 -r

3. Rebuild the index.

   • During DDL or DML operations, if index problems occur due to software or hardware faults, run the following command to rebuild the index:

     REINDEX TABLE tablename;

   • If the error message contains xxxx_index, the index of a user table is faulty. xxxx indicates the name of the user table. Run either of the following commands to rebuild the index:

     REINDEX INDEX indexname;

     Or

     REINDEX TABLE tablename;

   • If the error message contains pg_xxxx_index, the index of the system catalog is faulty. Run the following command to rebuild the index:

REINDEX SYSTEM databasename;