1. What is the purpose of an index in PostgreSQL database design?
2. What is the purpose of the "pg_stat_statements" extension in PostgreSQL?
3. What is "logical replication" in PostgreSQL?
4. In PostgreSQL, what is "failover" in the context of replication?
5. What is the purpose of PostgreSQL's "GRANT" and "REVOKE" statements in the context of security?
6. What does the "DELETE" statement in PostgreSQL do?
7. What is the "PostGIS" extension used for in PostgreSQL?
8. Which PostgreSQL tool provides a command-line interface for database administration and scripting tasks?
9. Which PostgreSQL command is used to back up a database cluster, including all databases and configuration files?
10. How can you install PostgreSQL on a Linux system?
11. What is the purpose of "replication slots" in PostgreSQL?
12. What is "streaming replication" in PostgreSQL?
13. Which SQL clause is used to pivot rows into columns in PostgreSQL?
14. Which geospatial format is supported by the "WKT" abbreviation in PostgreSQL's geospatial features?
15. In PostgreSQL's geospatial data management, what is "SRID" an acronym for?
16. In PostgreSQL security best practices, what does "least privilege" mean?
17. What does "hstore" data type provide in PostgreSQL's NoSQL features?
18. In PostgreSQL, what is the purpose of a foreign key constraint in a table?
19. What does a "pg_dumpall" command do in PostgreSQL backup?
20. What is the primary goal of continuous archiving and point-in-time recovery (PITR) in PostgreSQL backup and restore?