Package nz.org.riskscape.engine.join
package nz.org.riskscape.engine.join
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ClassDescription
JoinConditionbased on aRealizedExpressionJoinIndexerimplementation that builds an in-memory hash index of tuples when theJoinConditionis an equality filter.Can join a relation on to another relation, tuple at a time.Base class that collaborates with theDefaultJoinerto provide the rhs of a join, given the lhs.Cheap way of avoiding a full-on factory pattern thing - each Indexer implementation should offer a Constructor to build an indexer from the given arguments.Joins a single lhs value against a set of rhs values, emitting them if the join condition holds.JoinIndexerthat does nothing, so should always work, albeit slowlyAbstractJoinIndexerfor creating indexers that perform some kind of comparison with a boolean yieldingRealizedExpression.JoinIndexerimplementation that attempts to build an in-memory spatial index of the tuples for narrowing down the set of rhs tuples.