Suggested Certification for Oracle PL/SQL

Oracle Database: Advanced PL/SQL

Recommended Book for Oracle PL/SQL

★★★★☆
Check Amazon for current price
View Deal
On Amazon

Recommended Book 1 for Oracle PL/SQL

★★★★☆
Check Amazon for current price
View Deal
On Amazon

Recommended Book 2 for Oracle PL/SQL

★★★★☆
Check Amazon for current price
View Deal
On Amazon

Recommended Book 3 for Oracle PL/SQL

★★★★☆
Check Amazon for current price
View Deal
On Amazon

Note: *Check out these useful books! As an Amazon Associate I earn from qualifying purchases.

Interview Questions and Answers

Performance improvements can be achieved through: Using indexes effectively, minimizing network round trips, using bind variables to prevent SQL injection and improve query plan reuse, avoiding cursors when possible (using bulk operations instead), and optimizing SQL queries within PL/SQL blocks.

A nested table can grow dynamically without a predefined size limit. A varray, on the other hand, has a fixed size limit defined at the time of creation.

The `COMMIT` statement saves all changes made in the current transaction to the database, making them permanent.

The `ROLLBACK` statement undoes all changes made in the current transaction, restoring the database to its previous state before the transaction began.

Advantages include: Modularity, information hiding (only specified elements are exposed), performance improvement (packaged subprograms are loaded into memory together), and improved security (access can be controlled at the package level).

Dynamic SQL allows you to construct and execute SQL statements at runtime. This is useful when the structure of the SQL statement is not known until runtime.

You can use the `EXECUTE IMMEDIATE` statement or the `DBMS_SQL` package to execute dynamic SQL statements. `EXECUTE IMMEDIATE` is simpler for single-statement execution, while `DBMS_SQL` provides more control for complex scenarios.

Collections are composite data types that allow you to store and manipulate a group of elements of the same data type. Types of collections include associative arrays (index-by tables), nested tables, and varrays.

A procedure is used to perform an action and does not necessarily return a value. A function, on the other hand, is designed to return a single value. Functions can be called within SQL statements, while procedures typically cannot be.

Triggers are PL/SQL blocks that automatically execute in response to specific events (e.g., INSERT, UPDATE, DELETE) on a table or view. They are used to enforce business rules, audit data changes, or perform other tasks automatically.

Common trigger types include: BEFORE statement, AFTER statement, BEFORE row, and AFTER row triggers. Statement triggers execute once per triggering event, while row triggers execute once for each row affected by the triggering event.

A package is a schema object that groups logically related PL/SQL types, variables, constants, subprograms (procedures and functions), cursors, and exceptions. Packages promote modularity and reusability.

Exceptions are handled using the EXCEPTION block within a PL/SQL block. You can define specific exception handlers for named exceptions (e.g., NO_DATA_FOUND) or use a general exception handler for others.

Stored procedures and functions are named PL/SQL blocks that are stored in the database. Procedures can perform actions, while functions typically return a single value.

There are two main types: implicit cursors (automatically created by Oracle for single-row SQL statements) and explicit cursors (declared and managed by the programmer for multi-row SELECT statements).

Common data types include VARCHAR2, NUMBER, DATE, BOOLEAN, CHAR, LONG, and CLOB. PL/SQL also supports user-defined types, such as records and collections.

A PL/SQL block is structured into three sections: DECLARE (optional, for declaring variables), BEGIN (mandatory, containing the executable statements), and EXCEPTION (optional, for handling errors).

A cursor is a pointer to a private SQL area that stores information for processing a SQL statement. It allows you to retrieve multiple rows returned by a SELECT statement, one row at a time.

PL/SQL (Procedural Language/SQL) is Oracles procedural extension to SQL. It combines the data manipulation capabilities of SQL with the procedural features of programming languages.

Advantages include modularity, portability, tight integration with Oracle database, procedural capabilities, support for object-oriented programming, and enhanced security.

SQL is data oriented language.

- To write queries, construct and execute DDL and DML statements, SQL is used.



- PL/SQL is application oriented language.

- PL/SQL is used to write program blocks, functions, procedures, trigger

CHAR is used for storing fix length character strings. It will waste disk space if this type is used to store variable length strings.

Varchar stands for variable length character string. Both Varchar and Varchar2 are data types to store character

DDL - Data Definition Language consists of the SQL commands that can be used to define the database schema. is a syntax for creating and modifying database objects such as tables, indices, and users. Examples of DDL commands: Create, Drop, Alter, Truncate

Define business requirements first.

- SELECT fields instead of using SELECT *

- Avoid SELECT DISTINCT.

- Create joins with INNER JOIN (not WHERE)

- Use WHERE instead of HAVING to define filters.

- Use LIMIT to sample que

Data Integrity, Data Privacy, Data Consistency, Data is easily accessible with fast response times, Backup and Recovery, Easy Distribution.

Explain with examples that sync with the job description.

Explain specific instances with respect to the job JD.

(1) Choose the Right Technology when picking up a programming language, Database, Communication Channel.

(2) The ability to run multiple servers and databases as a distributed application over multiple time zones.

(3)Database backup, correcti

Software testing is called the process or method of identifying errors in an application or system, such that the application works according to the requirement of end-users. It is an examination carried out to provide users the information on the quality

Explain specific instances with respect to the job JD.

A good software engineer is someone who is not only competent to write code but also competent to create, produce and ship useful software.

NA

Use a phased life-cycle plan, Continuous validation, Maintain product control, Use the latest programming practices, Maintain clear accountability for results.

Software engineering always requires a fair amount of teamwork. The code needs to be understood by designers, developers, other coders, testers, team members and the entire IT team.

Schedule, Quality, Cost, Stakeholder Satisfaction, Performance

A software project manager determines the project specifications, builds the project team, draws up a blueprint for the whole project outlining the scope and criteria of the project, clearly communicates the project goals to the team; allocates budget, an

The most common software sizing methodology has been counting the lines of code written in the application source. Another approach is to do Functional Size Measurement, to express the functionality size as a number by performing Function point analysis.

The major parts to project estimation are effort estimation, cost estimation, resource estimate. In estimation, there are many methods used as best practices in project management such as-Analogous estimation, Parametric estimation, Delphi process, 3 Poin

software configuration management (SCM) is the task of tracking and controlling changes in the software code, part of the larger cross-disciplinary field of configuration management. Whereas change management deals with identification, impact analysis, do

Basecamp, Teamwork Projects, ProofHub, Zoho Projects, Nifty, Trello, JIRA, Asana, Podio, etc.

A feasibility study is a study that takes into account all of the related factors of a project — including economic, technological, legal, and scheduling considerations — to assess the probability of completing the project.

Functional requirements are the specifications explicitly requested by the end-user as essential facilities the system should provide. Non-functional requirements are the quality constraints that the system must satisfy according to the project contract,

Quality control can be described as part of quality management that is focused on fulfilling quality requirements. While quality assurance relates to how a process is performed or how a product is made.

Single Responsibility Principle (SRP), Open/Closed Principle (OCP), Liskov Substitution Principle (LSP), Interface Segregation Principle (ISP), Dependency Inversion Principle (DIP).