Book Image

Oracle Advanced PL/SQL Developer Professional Guide

By : Saurabh K. Gupta
Book Image

Oracle Advanced PL/SQL Developer Professional Guide

By: Saurabh K. Gupta

Overview of this book

PL/SQL (Procedural Language/Structured Query Language) is Oracle Corporation's procedural extension language for SQL and the Oracle relational database. Server-side PL/SQL is stored and compiled in the Oracle Database and runs within the Oracle executable. With this guide Oracle developers can work towards accomplishing Oracle 11g Advanced PL/SQL Professional certification, which is the second milestone for developers working at the Associate level. The Oracle Advanced PL/SQL Developer Professional Guide helps you master advanced PL/SQL concepts. Besides the clear and precise explanation on advanced topics, it also contains example code and demonstrations, which gives a sense of application and usage to readers.The book gives a deep insight that will help transform readers from mid-level programmers to professional database developers. It aims to cover the advanced features of PL/SQL for designing and optimizing PL/SQL code.This book starts with an overview of PL/SQL as the programming database language and outlines the benefits and characteristics of the language. The book then covers the advanced features that include PL/SQL code writing using collections, tuning recommendations using result caching, implementing VPD to enforce row level security, and much more. Apart from programming, the book also dives deep into the usage of the development tool SQL Developer, employing best practices in database environments and safeguarding the vulnerable areas in PL/SQL code to avoid code injection.
Table of Contents (22 chapters)
Oracle Advanced PL/SQL Developer Professional Guide
Credits
Foreword
About the Author
Acknowledgement
About the Reviewers
www.PacktPub.com
Preface
Index

Chapter 3, Using Collections


Question No.

Answer

Explanation

1

a and c

Associative arrays can have negative integer subscripts, positive integer subscripts and string subscripts.

As associative arrays are treated as local arrays, initialization is not required for them.

2

c

Nested tables are an unbounded collection which can grow dynamically.

3

a

Varrays are always dense collections. Sparse varray doesn't exist.

4

c and d

BOOLEAN and NUMBER are not suitable index types for an associative array.

5

a and c

Yes, varray limit can be increased during runtime using the ALTER TABLE statement.

If all the cells of a varray are populated with elements, LAST is equal to COUNT. This also holds true when the varray is empty.

6

b

The first DBMS_OUTPUT prints the first element from the default constructor. Once it is reassigned with a value in the executable section, the default values are overwritten.

7

a and c

Varrays are bounded collections which can accommodate data maximum up to the specified limit.

8

a, b, and c

EXISTS doesn't raises any exception.

DELETE cannot be used with varrays.