Question
$15.00 3-5 paragraphs Details: What are entit
- From Computer-Science: General-CS
- Closed, but you can still post tutorials
- Due on Jan. 14, 2011
- Asked on Jan. 11, 2011 at 07:20:52AM
Q:
3-5 paragraphs
Details: What are entity integrity and referential integrity? Why are they important for relational databases? Please provide examples for each to support your answers.
Assignment Guidelines:
Research entity integrity and referential integrity.
Explain why they are important to relational databases.
Provide at least one example for each.
Post your explanation and examples to a new Discussion Board topic.
Respond to two other students' Discussion Board posts.
$15.00
Integrity Referential Integrity Tutorial
- This tutorial was purchased 2 times and rated No Rating by students like you.
- Posted on Jan. 11, 2011 at 07:35:40AM
Posted by :
MrFarshay
Rating (304):A-
Questions Asked: 1
Tutorials Posted: 3919,
Blog Posts: 1,
Earned: $12,735.22
Rating (304):A-
Questions Asked: 1
Tutorials Posted: 3919,
Blog Posts: 1,
Earned: $12,735.22
A:
Preview: ... ach table in a database must have a primary key, this primary key can appear in other tables because of its relationship to data within those tables. When a primary key from one table appears in another table, it is called a foreign key .
Foreign keys join tables and establish dependencies between tables. Tables can form a hierarchy of dependencies in such a way that if you change or delete a row in one table, you destroy the meaning of rows in other tables. For example, Figure 353 shows that the customer_num column ...
The full tutorial is about 420 words long .
$12.00
go for it!!
- This tutorial hasn't been purchased yet.
- Posted on Jan. 11, 2011 at 07:39:50AM
A:
Preview: ... est i ...
The full tutorial is about 7 words long plus attachments.
entity integrity and referential integrity.docx (12K)