Listen Software Solution "How to" Series 1: Paradigm Outline

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Listen Software Solution "How to" Series 1: Paradigm Outline





General



The following paradigm outline usually means dividing a table into two or more tables with fewer columns, and designing a primary foreign key association in a smaller table. So they can be reconnected through the join operator. The advantage of partitioning tables is to reduce data redundancy.

The following is a brief overview of the standard paradigm:



First Paradigm

For each row in the table, you must have only a unique row value. Each column in a row has only a unique value and is atomic.



Second Normal form

The second normal form requires that a non-key column be a subset of the primary key, and that a non-key column activity must depend entirely on the entire primary key. Primary keys must have unique elements, and a primary key can consist of one or more columns that make up a unique value. Once created, the primary key cannot be changed, and the foreign key associates a table's primary key. A primary foreign key association means a one-to-many relationship.



Third normal form

The third paradigm requires that non-primary key columns are not dependent.



Form IV

The Forth paradigm prohibits a one-to-many relationship between primary key columns and non-primary key columns from being constrained



Form V

The V Paradigm splits the table into as small a block as possible, in order to exclude all redundancy in the table.

adjourned