After designing the E-R diagram, you need to convert it into tables in the relational model. There are some rules for converting the E-R diagram into tables. The goal is to use a set of transformation rules to transform the E-R design into a set of definitions for relational tables.
Transformation Rule 1
Rule 1 is to convert an entity into a table:
- Every entity in an E-R diagram is mapped to a single table.
- The columns of the table represent all the single-valued simple attributes that are attached to the entity.
- A primary identifier is mapped to a primary key.
- Entity occurrences are mapped to rows of the table.
student and employee, are mapped to two tables.
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Dear Algebra, Please stop asking us to find your X. She’s not coming back. Do’t ask y. |