Columns+and+rows

Rules
Relational databases must stick to the following rules:

1. Each table in the database must be identified by a unique name 2. Each column in a table must be identified by a unique name within that table 3. The data in each column of a table is same domain and type 4. Each row in a table is unique 5. Each cell in a table contains one value only 6. Rows and columns in a table can be in any order

Columns


See rule 2 above - column names within a table must have a unique name. There can only be one column named forename. See rule 3 above - data in each column must be of the same domain and data type. See rule 6 above - we can swap the order of the columns without having any impact on the data in the database.

Rows


See rule 4 above - data in each row of a table must be unique. There can be 2 Richie Grays born on 19/05/1998 but they would both have a different Pupil ID

See rule 5 above - each cell in a table can only contain one value. Richie Gray can have only one Pupil ID, one Forename, one Surname and one DOB.

See rule 6 above - we can swap the order of the cells without having any impact on the data in the database.