describe shorthand syntax for relations

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 # Relation: two dimensional table of data.
 
+## Shorthand syntax
+
 Employee1(id, name) # shorthand notation for describing a relation.
 
+* primary key is underlined.
+* foreign key uses a dashed underline.
+
+Employees( *id*, name )
+
 ## Relational Keys
 
 * primary key: attribute or combination of attributes that uniquely identifies each row in a relation.