1Z0-006 Database Concepts & Terminology 4

Question 1

What does DDL stand for in the context of SQL?

Accepted Answer

Data Definition Language

Answer

DDL (Data Definition Language) includes SQL statements like CREATE, ALTER, and DROP that define or modify the structure of database objects.

Question 2

Which SQL sublanguage includes the INSERT, UPDATE, and DELETE statements?

Accepted Answer

DML

Answer

DML (Data Manipulation Language) consists of statements that add, modify, or remove data rows within existing database tables.

Question 3

In an Entity-Relationship (ER) diagram, a weak entity is one that:

Accepted Answer

Cannot be uniquely identified without the primary key of another entity

Answer

A weak entity lacks a primary key of its own and depends on a related strong entity's primary key (called the owner entity) for its unique identification.

Question 4

What is the purpose of an index in a relational database?

Accepted Answer

To speed up data retrieval operations on a table

Answer

An index is a data structure that provides a fast lookup path to rows in a table, significantly improving query performance at the cost of additional storage and write overhead.

Question 5

Which concept refers to hiding the internal complexity of a database from end users and applications?

Accepted Answer

Abstraction

Answer

Data abstraction allows users and applications to interact with data at a high level without needing to know how it is physically stored or organized internally.

(1Z0-006) Oracle Database Foundations Associate Practice Test

(1Z0-006) Oracle Database Foundations Associate Practice Test

1Z0-006 Database Concepts & Terminology 4