Preview

03 - Flat file and relational databases

 1. A flat file database stores data in a ______ table structure. A relational database uses _______ table structures, cross-referencing records between tables

  initial / final

  multiple / single

  single / multiple

  final / initial

 2. The relational database model was developed and implemented in the early 1970's, primarily by ____

  Shell

  IBM

  Apple

  Tesla

 3. Flat file databases were a natural development early in computing history.
Flat file databases are typically plain text files that store one record
 per line, with record fields delimited by whitespace or a delimiting character. 
Flat file databases can be read directly by a variety of software applications.

  TRUE

  FALSE

 4. The primary feature of a relational database is its_________, which is a unique identifier assigned to every record in a table

  entity relationship

  index

  table structure

  primary key

 5. An example of a good primary key is a registration number. It makes every record ______, facilitating the storage of data in multiple tables, and every table in a relational database must have a primary key field.

  unique

  finite

  searchable

  appropriate

 6. Another key feature of relational databases is their ability to hold data over ______ tables.

  mulitple

  deletable

  sql

  duplicated

 7. The primary key can ________ in a one-to-one relationship, one-to-many relationship or many-to-many relationship

  join tables

  duplicate tables

  find indexes

  delete tables

 8. Relational databases enable users to delete, update, read and create data entries in the database tables. This is accomplished though structured query language, or _____________

  MCQ which is a type of question based search

  direct and manual look up - done by individuals that have the time to do so

  SQL, which is based on relational algebraic principles

  ENQ which has been developed by IBM

 9. In addition to the data tables, relational databases use _______ to quickly find records based on search criteria

  searches

  columns

  indexes

  capitals

 10. Relational databases generally require a relational database management system (RDBMS) to ______________________

  write SQL code

  create indexes

  manage and access data

  duplicate tables where necessary

 11. Flat file databases are simple and portable, and typically can be used without requiring special software

  TRUE

  FALSE

 12. Relational databases are faster, more efficient and more powerful than flat files. Most RDBMSs provide database access over networks.

  TRUE

  FALSE

 13. What is a disadvantage or potential difficulty that will arise for Company A as orders are placed?
Company A uses a flat file database with a single table named orders to record orders they receive, while Company B uses a relational database with two tables: orders and customers

  There are no disadvantages - as one table in this case would be the better option for multiple orders

  If customers place more than one order, their general information will need to be re-entered and thus duplicated for each order they place

  If customers place just one order, their records could end up being confused with another record

  If customers fail to place a record, they could face complete deletion from the database

 14. What are some of the disadvantages of duplication (that may arise in a flat file database)?

  Whenever there is duplicate data, as in the case above, many inconsistencies may arise when users try to query the database

  A single change of address would require finding all records in orders that the customer placed, and changing the address data for each one.

  A primary key may not be set and all customer data may not be unqiue in a flat file

  All of the listed options are valid

 15. Repeating data unnecessarily causing the creation of a database in which several rows have the same (repeating) data is called:

  data querying

  query deletion

  data duplication

  error repeating