Class MappingOpExtract.MyMappingRelation

java.lang.Object

se.liu.ida.hefquin.mappings.algebra.ops.MappingOpExtract.MyMappingRelation

All Implemented Interfaces:

MappingRelation

Enclosing class:

MappingOpExtract<DDS extends DataObject,DC1 extends DataObject,DC2 extends DataObject,QL1 extends Query,QL2 extends Query>

protected class MappingOpExtract.MyMappingRelation
extends Object
implements MappingRelation

Field Summary

Fields

Modifier and Type	Field	Description
protected MappingRelationCursor	cursor
protected final List<String>	schema

Fields inherited from interface se.liu.ida.hefquin.mappings.algebra.MappingRelation

errorNode, gAttr, oAttr, pAttr, sAttr, spogAttrs

Constructor Summary

Constructors

Constructor	Description
MyMappingRelation(DDS d)

Method Summary

Modifier and Type	Method	Description
MappingRelationCursor	getCursor()
List<String>	getSchema()	Returns the set of attributes for which the tuples in this relation have values.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

schema

protected final List<String> schema

cursor

protected MappingRelationCursor cursor

Constructor Details

MyMappingRelation

public MyMappingRelation(DDS d)

Method Details

getSchema

public List<String> getSchema()

Description copied from interface: MappingRelation

Returns the set of attributes for which the tuples in this relation have values. The returned list can be assumed to be duplicate free.

The order of the attributes in the returned list is relevant when accessing the values of the tuples via a cursor for this relation (see MappingRelationCursor.getValueOfCurrentTuple(int)).

Specified by:

getSchema in interface MappingRelation

getCursor

public MappingRelationCursor getCursor()

Specified by:

getCursor in interface MappingRelation