Lesson 2.1: 12 laws of Online Analytical Processing Flashcards
(30 cards)
Who worked out the theories of data arrangement, which issued the paper “A Relational Model of data for large shared data banks” in 1970?
Edgar Frank Codd
Codd continued to develop and extend his relational model, sometimes with collaboration with who?
Chris Date
What form was named after Codd?
Boyce-Codd Normal Form
It is designed to define what is required from a database management system in order for it to be considered relational, i.e., an RDBMS.
Codd’s 12 rules
T/F? The system must qualify as relational, as a database, and as a management system.
True
What rule contains all information in the database is to be represented in one and only way, namely by values in column positions within rows of tables.
Rule # 1, the information rule
What rule contains all data must be accessible with no ambiguity?
Rule # 2, the guaranteed access rule
What rule contains that the DBMS must allow each field to remain null (or empty)?
Rule # 3, systematic treatment of null values
What rule supports an online, inline, relational catalog that is accessible to authorized users?
Rule # 4, Active online catalog based on the relational model
The system must support at least one relational language that has what syntax?
linear syntax (part of rule # 5)
T/F System is not necessarily be used interactively or within application programs to be considered a RDBMS.
False. It must be used both interactively and within application programs (part of rule # 5)
T/F? RDBMS does not support data definition operations, data manipulation operations, security and integrity constraints, etc.
False. upports data definition operations (including view definitions), data manipulation operations (update as well as retrieval), security and integrity constraints, and transaction management operations (begin, commit, and rollback). (part of rule # 5)
It is a rule where all views that are theoretically updatable must be updatable by the system.
Rule # 6, the view updating rule
It is a rule where a system must support set-at-a-time insert, update, and delete operators.
Rule # 7, high-level insert, update, and delete
What is meant of a system must support set-at-a-time insert, update, and delete operators?
States that these operators should be supported for any retrievable set rather than just for a single row in a single table.
It is a rule where changes to the physical level (how the data is stored, whether in arrays or linked lists, etc.) must not require a change to an application based on the structure.
Physical data independence
It is a rule where Changes to the logical level (tables, columns, rows, and so on) must not require a change to an application based on the structure.
Logical data independence
T/F? Physical data independence is more easier to achieve than logical data independence.
True.
It is a rule where Integrity constraints must be specified separately from application programs and stored in the catalog.
Rule # 10, integrity independence
T/F? It must be not be possible to change such constraints as and when appropriate without unnecessarily affecting existing applications.
False. It must be possible.
It is a rule where the distribution of portions of the database to various locations should be invisible to users of the database
Rule # 11, Distribution independence
If the system provides a low-level (record-at-a-time) interface, then that interface cannot be used to subvert the system. What rule is this?
Rule # 12, The nonsubversion rule
Example of the nonsubversion rule? (R #12)
bypassing a relational security or integrity constraint
In the mid to late 1990s, businesses found it very difficult to query data out of their recently acquired relational databases transaction systems which ushered the rise of what called?
Online Analytical Processing or (OLAP)
