Basic Statements Flashcards
What is Structured Query Language (SQL), and how is it related to relational algebra queries?
Structured Query Language (SQL) is a user-friendly language for specifying relational algebra queries. It provides a more accessible and practical way for users to interact with relational databases compared to the abstract concepts of relational algebra.
Do all major database systems support SQL?
Yes, all major database systems support SQL. It has become a standard language for managing and interacting with relational databases.
What are the main components provided by SQL for database operations?
SQL provides three main components for database operations:
Data Manipulation Language (DML): Used for retrieving, inserting, and modifying database contents.
Data Definition Language (DDL): Used for adding and deleting database objects, such as tables and indexes.
Data Control Language (DCL): Used for configuring security access to the database.
What tasks can be accomplished using SQL’s Data Manipulation Language (DML)?
SQL’s Data Manipulation Language (DML) is used for tasks such as retrieving data from the database, inserting new records, and modifying existing records.
What is the role of Data Definition Language (DDL) in SQL?
Data Definition Language (DDL) in SQL is used to define and manage the structure of the database. It includes operations like creating tables, modifying table structures, and deleting tables.
