1. Codd's Rules
System support for undefined values
Rule 3
Command used to create a table
CREATE TABLE
Which symbol is used to select the entire table in the SELECT command?
*
What must every table have?
PRIMARY KEY and FOREIGN KEY
Which command gives a result between two values?
BETWEEN
Information rule – all information in a relational database is represented in tables, including field names
Rule 1
The first step in managing data in a database
CREATE DATABASE
What are the default keywords of the SELECT command?
FROM and WHERE
What types of relationships exist between the primary and foreign key?
1:1, 1:N, N:M
Which command give data placed within the argument?
IN
Guaranteed access rule – every value in a relational database can be accessed using the table name, primary key value, and field name
Rule 2
A constraint that uniquely identifies each row in a database table
UNIQUE
Which command includes duplicates?
SELECT ALL
Which normal form ensures atomicity of data?
1 NF
Which operator gives the result of two queries?
UNION
Insert, update, and delete operations are performed at the set level
Rule 7
How many data types exist?
8
Which command selects only the first n records?
SELECT TOP
In which normal form must data represent only one subject?
2 NF
Which command keeps duplicate data?
UNION ALL
Logical data independence – changes to table structure do not affect applications
Rule 9
Between which numbers does a float with 8 bits range?
[25,53]
Which command removes duplicates?
DISTINCT
In which normal form must all calculations be removed from tables?
3 NF
Which command gives the result of the intersection?
INTERSECT