U2 - Ch.5 - Database Structures

Question 1

What is the general purpose of a database?

Answer 1

To organize and keep track of things. Notably, to keep track of multiple themes.

Question 2

What’s a theme? What kinds of systems are used for a single theme vs multiple themes.

Answer 2

A theme is any piece of information. A single theme would be student’s grade, while multiple themes may be the student’s address, phone number, etc.

Spreadsheets can be used for a single theme, while databases are to be used for multiple themes.

Question 3

What is intellectual property?

Answer 3

Any creative content that can be protected through a trademark, patent, copyright, etc.

Question 4

What is content?

Answer 4

Something of value, can be considered an asset.

Eg. data, documents, tweets. etc.

Question 5

What is a CMS?

Answer 5

A content management system that allows users to load/review/edit creative content. `

Question 6

Define a database?

Answer 6

A self-describing collection of integrated records

Question 7

Draw the hierarchy of data elements

Answer 7

1. Byte (character of data)
2. Bytes are grouped into column/fields
3. Columns are grouped into rows/records
4. Rows are grouped into tables/files

Question 8

What is a field?

Answer 8

A field is a column of data (eg. student numbers of all students).

Question 9

What is a record?

Answer 9

A row of data (eg all the student info of a particular student)

Question 10

What are the components of a database?

Answer 10

A collection of tables, relationships among rows in tables, and metadata.

Question 11

What is metadata?

Answer 11

Metadata is data that describes data. It basically describes what type of information is in a certain column or field.

Question 12

What are keys, foreign keys and relational databases?

Answer 12

A key is a column that identifies unique rows in a table. Each table has a key.

A foreign key is a key in a different table than the one in which it originally resides in (usually to identify and relate data from other tables).

Relational database is a database that uses tables, keys and foreign keys.

Question 13

What is a DBMS?

Answer 13

A database management system is a program that creates, processes and administers a database. Eg. (Oracle and IBM).

Question 14

What are 3 main functions of DBMS?

Answer 14

1. Create the database and its structures (building relationships and tables).
2. Processing the database (editing, updating, modifying, deleting data in the database, can be done with SQL)
3. Administer the database (setup security, back-ups, passwords, etc.)

Question 15

What is a database application?

Answer 15

A collection of forms, queries, reports, and application programs that process a database.

Question 16

What’s the difference between forms, reports and queries?

Answer 16

Forms: used to read, insert, modify and delete data.

Reports: present data in a nicely readable fashion

Queries: means of getting answers from database data

Question 17

Describe the lost-update problem.

Answer 17

When two users are accessing the database at the same time, only one user can change data.

The updates done by additional users end up getting lost because of this.

Thus some mechanism of locking (such that only one user can access the database at a time) is needed to prevent this issue.

Question 18

Difference between Enterprise DBMS and Personal DBMS.

Answer 18

Enterprise supports larger organizations (i.e. > 100), while personal suffices for < 100 users (usually < 15).

Question 19

What’s an ACID transaction?

Answer 19

Atomic, consistent, isolated & durable. AKA All-or-none transaction processing.

Question 20

noSQL vs NewSQL (DBMS)

Answer 20

NoSQL is non-relational, high transaction rates, and simple data structures (no ACID support).

NewSQL have high transactions, ACID support and may be relational.