PostgreSQL Objective Questions & Answers for Professionals Set-1
1. Which PostgreSQL utility is used to perform logical replication between databases?
Explanation: The pg_logical extension in PostgreSQL enables logical replication, allowing selective replication of specific tables or changes based on replication rules.
2. Which parameter in PostgreSQL controls the amount of memory used for sorting operations?
Explanation: The "work_mem" parameter in PostgreSQL controls the amount of memory used for sorting operations and hash tables during query execution
3. Which query optimization technique in PostgreSQL allows combining multiple sequential scans into a single scan?
Explanation: The "Bitmap heap scan" in PostgreSQL allows combining multiple sequential scans into a single scan using bitmaps, improving query performance.
4. Which PostgreSQL configuration parameter determines the maximum number of simultaneously allowed connections to the database server?
Explanation: The "max_connections" parameter in PostgreSQL sets the maximum number of concurrent connections allowed to the database server.
5. Which PostgreSQL extension is used to handle hstore (key-value) data efficiently?
Explanation: The "pg_hstore" extension in PostgreSQL provides support for storing and querying hstore (key-value) data efficiently.
6. Which parameter controls the checkpoint behavior in PostgreSQL?
Explanation: The "checkpoint_timeout" parameter in PostgreSQL controls the time interval between automatic checkpoints.
7. Which PostgreSQL extension is used to manage background workers and perform parallel processing tasks?
Explanation: The "pg_bgworker" extension in PostgreSQL allows managing background worker processes and performing parallel processing tasks.
8. Which statement is used to create a new user-defined data type in PostgreSQL?
Explanation: The "CREATE TYPE" statement in PostgreSQL is used to create a new user-defined data type.
9. What is the purpose of the "pg_ident.conf" file in PostgreSQL?
Explanation: The "pg_ident.conf" file in PostgreSQL is used to map operating system users to specific database users for authentication.
10. In PostgreSQL, which function is used to return the current timestamp?
Explanation: The "NOW()" function in PostgreSQL is used to return the current timestamp.
11. Which PostgreSQL extension provides support for handling arrays?
Explanation: The "intarray" extension in PostgreSQL provides support for handling arrays, including indexing and querying.
12. Which operator in PostgreSQL is used for array containment check?
Explanation: The "@>" operator in PostgreSQL is used for array containment check, i.e., it checks if an array contains a specific element or another array.
13. What is the purpose of the "pg_visibility" extension in PostgreSQL?
Explanation: The "pg_visibility" extension in PostgreSQL is used to analyze and understand the visibility of data in transactions.
14. In PostgreSQL, which function is used to generate a sequence of values?
Explanation: The "NEXTVAL()" function in PostgreSQL is used to generate the next value in a sequence.
15. Which configuration parameter in PostgreSQL controls the amount of memory used for maintenance tasks such as vacuuming and indexing?
Explanation: The "maintenance_work_mem" parameter in PostgreSQL controls the amount of memory used for maintenance tasks like vacuuming and indexing.
Related content
Rate Your Experience
: 89
: 1