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Collection of less common used parameters of pg_dump and pg_restore

pg_dump and pg_restore are command-line utilities provided by PostgreSQL for backup and restore operations. While some parameters are commonly used, there are less common parameters that can be valuable in specific situations. Here are 10 less commonly used parameters for pg_dump and pg_restore, along with examples and explanations:

pg_dump Parameters:

1. –quote-all-identifiers:

   • Usage: Encloses all object names (tables, columns, etc.) in double quotes, even if they are not case-sensitive or contain special characters.
   • Example:

     pg_dump --quote-all-identifiers -d mydb -f backup.sql
     

     This ensures that all identifiers are consistently quoted in the dump.

2. –no-security-labels:

   • Usage: Excludes security labels (if any) from the dump. Security labels are used for Mandatory Access Control (MAC) policies.
   • Example:

     pg_dump --no-security-labels -d mydb -f backup.sql
     

     Use this when you don’t need to preserve security labels during the dump.

3. –lock-wait-timeout=seconds:

   • Usage: Specifies the maximum time (in seconds) to wait for a lock to be acquired. Useful for preventing long waits during the dump.
   • Example:

     pg_dump --lock-wait-timeout=10 -d mydb -f backup.sql
     

     This sets a 10-second timeout for waiting on locks.

4. –no-comments:

   • Usage: Excludes comments (e.g., object descriptions) from the dump, reducing the dump’s size.
   • Example:

     pg_dump --no-comments -d mydb -f backup.sql
     

     This omits all comments in the dump.

5. –if-exists:

   • Usage: Adds “IF EXISTS” clauses to the SQL statements when creating objects, preventing errors if objects already exist.
   • Example:

     pg_dump --if-exists -d mydb -f backup.sql
     

     This is useful when restoring into a schema with potentially existing objects.

pg_restore Parameters:

6. –single-transaction:

   • Usage: Executes the restore within a single transaction, ensuring that either all changes are applied or none at all.
   • Example:

     pg_restore --single-transaction -d mydb backup.sql
     

     Use this for atomic restores when multiple statements are involved.

7. –no-role-passwords:

   • Usage: Omits passwords for roles (users) when restoring. Useful when the passwords are managed separately.
   • Example:

     pg_restore --no-role-passwords -d mydb backup.sql
     

     This avoids setting passwords during restore.

8. –if-not-exists:

   • Usage: Adds “IF NOT EXISTS” clauses to SQL statements when creating objects, preventing errors if objects already exist.
   • Example:

     pg_restore --if-not-exists -d mydb backup.sql
     

     Similar to --if-exists, but for restore operations.

9. –no-comments:

   • Usage: Excludes comments from SQL statements during restore, even if they were included in the dump.
   • Example:

     pg_restore --no-comments -d mydb backup.sql
     

     Useful to skip comment restoration.

10. –disable-triggers:

    • Usage: Temporarily disables triggers during data loading. This can be helpful for bulk data imports.
    • Example:

      pg_restore --disable-triggers -d mydb backup.sql
      

      Triggers are re-enabled after data load.

These less commonly used parameters provide additional flexibility and control over the behavior of pg_dump and pg_restore. Depending on your specific requirements, you may find these options helpful for customizing backup and restore processes in PostgreSQL.