PNB MetLife Senior Plsql Developer Interview Questions, Process, and Tips

Hard parse is when SQL statement is parsed every time it is executed. Soft parse is when SQL statement is parsed only once.

• Hard parse is resource-intensive and can slow down performance.

• Soft parse is faster and more efficient.

• Hard parse occurs when there is a syntax error or when the SQL statement is not in the shared pool.

• Soft parse occurs when the SQL statement is already in the shared pool.

• Hard parse can be avoided ...read more

A dirty block is a database block that has been modified but not yet written to disk.

• Dirty blocks are a common occurrence in database systems.

• They can cause performance issues if not managed properly.

• Dirty blocks are typically written to disk during a checkpoint process.

• If a dirty block is lost due to a system failure, data loss can occur.

Control file is a configuration file used by Oracle database to manage the physical structure of the database.

• It contains information about the database such as datafiles, redo log files, and control files.

• It is created during database creation and is read by the database at startup.

• It is used to manage the physical structure of the database and to recover the database in case of a failure.

• It is edited using a text edi...read more

Performance tuning involves optimizing the code and database to improve system speed and efficiency.

• Identify bottlenecks in the system

• Optimize SQL queries and indexes

• Use caching and memory management techniques

• Reduce network latency and disk I/O

• Monitor system performance regularly