what type of diagram shows the relationships between tables
Entity–relationship model An ER model is typically implemented as a database. In a simple relational database implementation, each row of a table represents one instance of an entity type, and each field in a table represents an attribute type. In a relational database a relationship between entities is implemented by storing the primary key of one entity as a pointer or "foreign key" in the table of another entity
Twelve Tables According to Roman tradition, the Law of the Twelve Tables (Latin: Leges Duodecim Tabularum or Duodecim Tabulae) was the legislation that stood at the foundation of Roman law. The Tables consolidated earlier traditions into an enduring set of laws.[1][2]