• PROJECT a subset of attributes for all tuples from a relation
• Pi (p)
• p_{<attribute list>}(R)
• If sublist is only non-key attributes
• might get duplicates
• Removes duplicates
• Attribute list:sublist example

The result set of the operation is itself a relational. That output relation will contain the same number of rows as the input, however it may contain a different number of columns; fewer if a subset of attributes is projected; more if derived or aggregated attributes are included.