Muscle atrophy, or muscle wasting, results from loss of muscle tissue. Little or no physical exercise and a sedentary lifestyle are common causes of muscle atrophy, in this case called disuse atrophy.
PRIMARY KEY Constraints. A table typically has a column or combination of columns that contain values that uniquely identify each row in the table. This column, or columns, is called the primary key (PK) of the table and enforces the entity integrity of the table.
A foreign key is a key field that identifies a record in another table. Understanding the difference between a primary key and a foreign key will be useful when dealing with many-to-many relationships in FileMaker Pro. Relational database design supports many different types of relationships between tables.