Physical Operators

The main Java interface for the physical operators of HeFQUIN is called PhysicalOperator, and the relevant classes that implement this interface can be found in the se.liu.ida.hefquin.engine.queryplan.physical.impl package. The physical operators that we currently have are the following (look at their Javadoc comments for a detailed description):

nullary operators

• request

unary operators

• brTPF-based bind join
• FILTER-based bind join
• UNION-based bind join
• VALUES-based bind join
• request-based nested loops join (rNLJ)
• parallel multi-left join
• filter
• g2l
• l2g

binary operators

• naive (local) nested loops join (NLJ)
• hash join for inner join
• hash join for right-outer join
• symmetric hash join (SHJ)
• binary union

n-ary operators

• multi-way union