PL/SQL is Oracle's procedural extension to SQL, used heavily in enterprise and database-centric roles. Its interviews test the block structure, stored procedures vs functions, cursors, triggers, and exception handling. Here are the PL/SQL interview questions that actually get asked, with answers. (See also our SQL and DBMS guides.)
Fundamentals
- What is PL/SQL, and how does it differ from SQL?
- The block structure — declare, begin, exception, end.
- What are %TYPE and %ROWTYPE?
- Anonymous blocks vs named blocks.
Procedures, functions & cursors
- Stored procedure vs function — key differences.
- IN, OUT, and IN OUT parameters.
- What is a cursor — implicit vs explicit?
- Cursor FOR loops; the FOR UPDATE / WHERE CURRENT OF clauses.
Triggers, exceptions & packages
- What is a trigger, and BEFORE vs AFTER, row vs statement?
- Exception handling — predefined vs user-defined exceptions.
- What is a package (specification and body)?
- What is a mutating table error?
How to prepare
PL/SQL rounds probe procedures, cursors, and triggers verbally. Practise explaining the differences and use cases out loud. Greenroom runs spoken technical interviews that follow up on your reasoning. Pair it with our SQL and DBMS guides.
Frequently asked questions
What are the most common PL/SQL interview questions?
Common PL/SQL questions cover what PL/SQL is and how it differs from SQL, the block structure (declare, begin, exception, end), %TYPE and %ROWTYPE, stored procedures vs functions, parameter modes (IN, OUT, IN OUT), cursors (implicit vs explicit, cursor FOR loops), triggers (BEFORE vs AFTER, row vs statement), exception handling, packages, and mutating table errors.
What is the difference between a procedure and a function in PL/SQL?
A procedure performs an action and may return values through OUT parameters, but doesn't return a value directly, so it's called as a standalone statement. A function must return a single value via a RETURN statement and can be used within SQL expressions and queries. In short, use a function when you need a value back inline, and a procedure for performing operations or returning multiple values via OUT parameters.
What is a cursor in PL/SQL?
A cursor is a pointer to the result set of a query, letting you process rows one at a time. Implicit cursors are created automatically for single-row DML and SELECT INTO statements, while explicit cursors are declared by you to iterate over multi-row result sets using OPEN, FETCH and CLOSE (or a cursor FOR loop). Explicit cursors give fine-grained control over row-by-row processing.
How should I prepare for a PL/SQL interview?
Focus on the block structure, procedures vs functions, cursors, triggers and exception handling, understanding when and why to use each rather than just syntax. Practise explaining the differences and real use cases out loud with a voice-based mock interview that follows up, since PL/SQL rounds probe procedural database programming concepts verbally.