Database Systems Flashcards

Flashcards about Database Systems based on lecture notes.

What is the difference between data and information?

Information is processed, organized, and structured data, whereas data is raw, unorganized facts that need to be processed.

What is a database?

A collection of information that exists over a long period of time and is managed by a DBMS.

What is a Database Management System (DBMS)?

A software package/system to facilitate the creation and maintenance of a computerized database.

What is a Database System?

The DBMS software together with the data itself; sometimes, the applications are also included.

What is the expected functionality of a DBMS?

Allow users to create new databases and specify their schemas, give users the ability to query the data, support the storage of very large amounts of data, enable durability, and control access to data from many users at once.

What is the Hierarchical data model?

Tree-based model used in early mainframe DBMS; an example is the IBM Information Management System (IMS).

What is the Network data model?

Graph-based model invented by Charles Bachman in the late 1960s, allowing each record to have multiple parent and child records but not supporting high-level query language.

What are Relational Database Systems?

Defined by Edgar Frank "Ted" Codd in the 1970s based on relations; SQL was developed, and Oracle v.2 was the first commercial RDBMS product using SQL.

What is Information Integration in the context of databases?

Used to join the information contained in many related databases into a whole, often involving data warehouses or middleware.

Who are the main types of Database Users?

Database Administrators, Database Designers, and Database End users.

What are DDL (Data Definition Language) Commands?

Commands used for defining data structure; examples include CREATE, ALTER, DROP.

What are DML (Data Manipulation Language) Commands?

Commands used to retrieve, insert, delete, and update data; they do not affect the schema but affect the content or extract data.

What is the process of Answering the query in DBMS?

Parsing and optimizing a query, resulting in a query plan executed by the execution engine.

What is Transaction processing in DBMS?

A group of database operations processed by a transaction manager.

Name some examples of Non-relational databases (NoSQL).

MongoDB and Redis.

Name some examples of Multi-model databases.

Oracle database and ArangoDB.