Building Tables
From Compsci1
(Difference between revisions)
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Important to remember - each subject of a database is represented by a table in the database, each characteristic of a subject represents a field in the corresponding table. | Important to remember - each subject of a database is represented by a table in the database, each characteristic of a subject represents a field in the corresponding table. | ||
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| - | + | So, | |
| - | + | *One table, One subject | |
| + | |||
| + | *One field, One value | ||
| + | |||
| + | *One table, One primary key | ||
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| + | [[Databases]] | ||
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| + | --mickdemp 16:53, 19 October 2006 (EDT) | ||
Current revision as of 20:53, 19 October 2006
First we start with a flat database - a database consisting of a single table. Problems that can occur with a poorly designed table is
- - Redundancy - unnessesary duplication of data in the database
- - Multivalue field - a field that contains multiple values
- - Multipart field - a field that contains more than one data item.
Important to remember - each subject of a database is represented by a table in the database, each characteristic of a subject represents a field in the corresponding table.
So,
- One table, One subject
- One field, One value
- One table, One primary key
--mickdemp 16:53, 19 October 2006 (EDT)
