Accenture Plsql Developer Interview Questions and Answers

A view is a virtual table created by a query. It does not store data itself but displays data from one or more tables. Views can be used for querying data as if it were a table.

• Views are created using a SELECT statement with optional joins, WHERE clauses, etc.

• Views can simplify complex queries by pre-defining joins and filters.

• Views do not store data themselves, they display data from underlying tables.

• Views can be upd...read more

A synonym is an alternative name for a table, view, sequence, or other database object.

• Synonyms can be used to provide a different name for an object, making it easier to reference.

• They can be created to reference objects in other schemas or databases.

• Synonyms can be public (accessible to all users) or private (accessible only to the creator).

A sequence is a database object in Oracle that generates unique numbers in a specified order.

• Used to generate unique numbers for primary key columns

• Can be used in INSERT statements to automatically generate values

• Can be defined to increment by a specific value and start at a specific number

Procedures are named PL/SQL blocks that perform a specific task. They can accept parameters and return values.

• Procedures are stored in the database and can be called by other PL/SQL blocks or applications.

• They can accept input parameters to perform operations and can also return output values.

• Procedures help in modularizing code and promoting reusability.

• Example: CREATE PROCEDURE calculate_salary (emp_id IN NUMBER) IS ...read more

Procedures do not return any value while functions return a value.

• Procedures are used to perform an action, while functions are used to calculate and return a value.

• Procedures do not have a return statement, while functions must have a return statement.

• Functions can be called from SQL queries, while procedures cannot be called directly in SQL queries.

Partitions in PL/SQL are used to divide a table into smaller, more manageable pieces.

• Partitions help improve query performance by allowing data to be stored in separate segments based on a specified criteria.

• Common partitioning methods include range, hash, list, and composite partitioning.

• Example: Partitioning a sales table by month can improve query performance when searching for sales data within a specific time fram...read more

PL/SQL is a procedural extension of SQL used for writing stored procedures, functions, triggers, and packages in Oracle databases.

• PL/SQL allows for procedural programming, including loops, conditions, and exception handling.

• SQL is a declarative language used for querying and manipulating data in databases.

• PL/SQL code is executed on the server side, while SQL queries are executed on the client side.

• PL/SQL can be used to...read more

Performance tuning is the process of optimizing the speed and efficiency of a database system.

• Identifying and resolving bottlenecks in the database system

• Optimizing SQL queries for better performance

• Improving indexing and partitioning strategies

• Monitoring and analyzing system performance metrics

• Utilizing tools like explain plan and SQL tuning advisor

• Implementing caching mechanisms to reduce data retrieval time