Oracle Pl Sql Developer Interview Preparation

Top 20 Oracle Pl Sql Developer Interview Questions and Answers

If you are an Oracle PL/SQL Developer who is preparing for an interview or simply wants to improve your skills, it’s crucial to have some knowledge about the most common interview questions. By doing so, you can impress your potential employer with your expertise and get the job you want.

Question 1: What is PL/SQL?

PL/SQL stands for Procedural Language/Structured Query Language. It’s a programming language that includes SQL statements within its syntax. It’s specifically designed for the Oracle Database, and it’s commonly used to create stored procedures, functions, and triggers.

Question 2: What are the benefits of PL/SQL?

Question 3: What’s the difference between SQL and PL/SQL?

SQL is primarily used for managing data in a relational database while PL/SQL is a procedural language used to manage data in an Oracle database, enabling you to execute SQL statements, business logic, and control structures.

Question 4: What are the types of cursors available in PL/SQL?

Question 5: What is the difference between a package and a procedure?

Both are database objects. A package is a container of variables, cursors, and procedures. Procedures are sets of SQL statements that perform a particular task.

Question 6: What is a trigger?

A trigger is a special type of stored procedure that gets executed automatically when a specific event occurs. This could be DML operations such as INSERT, UPDATE, or DELETE on tables or views.

Question 7: What is a mutation error?

A mutation error occurs when a trigger tries to modify the same table that was used to fire the trigger. PL/SQL raises this error to avoid infinite loop possibilities.

Question 8: What is a cursor in PL/SQL?

A cursor is a pointer to a private SQL area where the data returned by a SELECT statement is stored. You can use it to manipulate the data returned by the SQL statement.

Question 9: How do you handle exceptions in PL/SQL?

You can handle exceptions using the EXCEPTION block. When an exception is raised, the control transfers to this block where you can write code to handle the error accordingly.

Question 10: What is a nested table?

A nested table is a single-column table that is an unordered set of elements. It provides a way to store multiple values in a single column, which is useful when storing non-scalar data types such as objects, collections, or strings.

Question 11: What is the difference between a collection and a varray?

A collection is an unordered set of elements of the same type. A varray (short for "variable size array") is an ordered set of elements of the same type but with a defined maximum size.

Question 12: What are the various types of collections in PL/SQL?

Question 13: What is the difference between an IN and OUT parameter?

An IN parameter can be referenced inside the procedure or function, but the value remains the same as the one passed in. An OUT parameter starts with a default value, which can be modified inside the procedure or function, and its value is returned to the caller.

Question 14: What does Autonomous Transaction mean?

Autonomous Transaction is a concept used in PL/SQL that allows a subprogram to commit or rollback its work independently of the main transaction. The main transaction is not affected by the changes made by the subprogram in the Autonomous Transaction.

Question 15: What is pragma in PL/SQL?

Pragma is a special instruction that provides additional information to the compiler without affecting the program’s logic. It’s used to specify the optimizer behavior, security checks, or debugging information for the program.

Question 16: What is a bulk binding?

Bulk binding is a technique that allows multiple rows of data to be processed in a single DML statement, resulting in a significant reduction of context switches and overheads. It makes the program more efficient and scalable.

Question 17: What is the difference between the EXCEPTION and RAISE_APPLICATION_ERROR?

The EXCEPTION handler traps exceptions raised in the program, while RAISE_APPLICATION_ERROR raises a user-defined exception and allows you to specify an error message and error number.

Question 18: What are the different types of SQL commands in PL/SQL?

Question 19: Can PL/SQL access remote databases?

Yes, PL/SQL can access remote databases using database links.

Question 20: What is dynamic SQL?

Dynamic SQL is a technique in PL/SQL that allows you to create SQL statements dynamically at runtime. It’s useful when the schema or table or column names are not available at compile time, or when you need to generate SQL statements based on input variables.

In conclusion, if you’re preparing for a PL/SQL interview, these questions and answers are an excellent starting point for improving your knowledge and confidence. Remember to practice your skills, always be up-to-date with the new features and updates of the language, and impress your potential employer with your expertise!

How to Prepare for Oracle Pl Sql Developer Interview

Oracle PL/SQL developers are responsible for designing and implementing efficient and scalable database solutions. They work with the Oracle database management system and develop PL/SQL code to enhance the functionality of applications that use the database. If you are looking for a job as a PL/SQL developer, here are some tips to help you prepare for the interview:

1. Brush up on your PL/SQL knowledge

2. Practice coding exercises

3. Familiarize yourself with Oracle database concepts

4. Prepare for questions related to job requirements

5. Research the company and the position

Remember to dress appropriately and be on time for the interview. Be prepared to demonstrate your knowledge and experience with PL/SQL development and Oracle database management. With these tips, you should be well on your way to success in your Oracle PL/SQL developer interview.