Examples of cascading.pipe.joiner.MixedJoin

cascading.pipe.joiner.MixedJoin

Class MixedJoin will return an {@link java.util.Iterator} that will iterate over a given{@link Joiner} and return tuples that represent a join as defined by the given boolean array.

So if joining three streams, {@code} boolean []true,false,false}} will result in a 'inner', 'outer', 'outer' join.

Joins perform based on the equality of the join keys. In the case of null values, Java treats two null values as equivalent. SQL does not treat null values as equal. To produce SQL like results in a given join, a new {@link java.util.Comparator} will need to be used on the joined values to prevent null fromequaling null. As a convenience, see the {@link cascading.util.NullNotEquivalentComparator} class.

    Pipe pipeUpper = new Each( new Pipe( "upper" ), new Fields( "line" ), splitter );


    Pipe[] pipes = Pipe.pipes( pipeLowerOffset, pipeUpper, pipeLower );
    Fields[] fields = Fields.fields( new Fields( "num" ), new Fields( "num" ), new Fields( "num" ) );


    MixedJoin join = new MixedJoin( new boolean[]{MixedJoin.OUTER, MixedJoin.INNER, MixedJoin.OUTER} );
    Pipe splice = new CoGroup( pipes, fields, Fields.size( 6 ), join );


    Flow flow = getPlatform().getFlowConnector().connect( sources, sink, splice );


    flow.complete();

    Pipe pipeUpper = new Each( new Pipe( "upper" ), new Fields( "line" ), splitter );


    Pipe[] pipes = Pipe.pipes( pipeLowerOffset, pipeUpper, pipeLower );
    Fields[] fields = Fields.fields( new Fields( "num" ), new Fields( "num" ), new Fields( "num" ) );


    MixedJoin join = new MixedJoin( new boolean[]{MixedJoin.OUTER, MixedJoin.INNER, MixedJoin.OUTER} );
    Pipe splice = new HashJoin( pipes, fields, Fields.size( 6 ), join );


    Flow flow = getPlatform().getFlowConnector().connect( sources, sink, splice );


    flow.complete();

Examples of cascading.pipe.joiner.MixedJoin

Related Classes of cascading.pipe.joiner.MixedJoin