This is a list of top PL-SQL interview questions and answers compiled by industry experts working in the PL/SQL domain. From these interview questions, you will understand 'what is the importance of PL/SQL?', database triggers, PL/SQL compilation process, PL/SQL packages, tracing a PL/SQL code, PL/SQL functions and procedures, and Joins and Views in PL/SQL. Learn PL/SQL from Intellipaat's PL/SQL Certification Training to excel in your career!
Oracle PL/SQL is a procedural language that has both interactive SQL and procedural programming language constructs such as iteration and conditional branching.
Go through this PL/SQL Tutorial to learn ‘What is PL/SQL?’
PL/SQL uses a block structure as its basic structure. Anonymous blocks or nested blocks can be used in PL/SQL.
A PL/SQL program unit associated with a particular database table is called a database trigger. It is used for:
Any constant, variable, or parameter has a data type depending on which the storage constraints, format, and the range of values and operations are determined.
The compilation process includes syntax check, bind, and p-code generation processes. Syntax checking checks the PL/SQL codes for compilation errors. When all errors are corrected, a storage address is assigned to the variables that hold data. It is called Binding. P-code is a list of instructions for the PL/SQL engine. P-code is stored in the database for named blocks and is used the next time it is executed.
Go through the Handling PL/SQL Errors tutorial page to know how error handling is done in PL/SQL!
A PL/SQL package consists of:
Check out the insightful PL/SQL tutorial to learn more about Pl/SQL Packages!
PL/SQL packages provide several benefits as follows:
Master PL/SQL from this top-rated PL/SQL Certification Training!
Tracing the code is a crucial technique to measure its performance during the runtime. Different methods for tracing the code includes:
A stored procedure is a sequence of statements or a named PL/SQL block that performs one or more specific functions. It is similar to a procedure in other programming languages. It is stored in the database and can be repeatedly executed. It is stored as a schema object. It can be nested, invoked, and parameterized.
Wish to learn more? Visit the PL/SQL Collections and Records tutorial page!
A cursor is a temporary work area created in system memory when a SQL statement is executed. A cursor contains information on a select statement and the row of data accessed by it. This temporary work area stores the data, retrieved from the database, to manipulate it. A cursor can hold more than one row but can process only one row at a time. A cursor is required to process rows individually for queries.
Select * from emp where sal= (select max(sal) from emp)
If you have any doubts or queries related to PL/SQL, get them clarified from our PL/SQL experts on our SQL Community!
Use the following code for displaying the highest salary from an employee table:
Select max(sal) from emp;
Select max(sal) from emp where sal not in ( select max(sal) from emp
Join is a keyword used to query data from multiple tables based on the relationship between the fields of tables. Keys play a major role in Joins.
A subquery is a query within another query. The outer query is known as the main query and the inner query is called the subquery. A subquery is executed first, and the result of the subquery is passed to the main query.
There are two types of subqueries: correlated and non-correlated
A trigger is a database object that automatically executes in response to some events on the tables or views. It is used to apply the integrity constraint to the database objects.
Very useful…Thanks for sharing….
Your email address will not be published. Required fields are marked *
Solve : * 11 + 2 =