com.mckoi.database
Class QueryPlan.MarkerNode

java.lang.Object
  extended by com.mckoi.database.QueryPlan.SingleQueryPlanNode
      extended by com.mckoi.database.QueryPlan.MarkerNode
All Implemented Interfaces:
QueryPlanNode, java.io.Serializable, java.lang.Cloneable
Enclosing class:
QueryPlan

public static class QueryPlan.MarkerNode
extends QueryPlan.SingleQueryPlanNode

A marker node that takes the result of a child and marks it as a name that can later be retrieved. This is useful for implementing things such as outer joins.

See Also:
Serialized Form

Field Summary
 
Fields inherited from class com.mckoi.database.QueryPlan.SingleQueryPlanNode
child
 
Constructor Summary
QueryPlan.MarkerNode(QueryPlanNode child, java.lang.String mark_name)
          Constructor.
 
Method Summary
 java.lang.Object clone()
          Deep clone.
 Table evaluate(QueryContext context)
          Evaluates the node and returns the result as a Table.
 java.lang.String titleString()
           
 
Methods inherited from class com.mckoi.database.QueryPlan.SingleQueryPlanNode
child, debugString, discoverCorrelatedVariables, discoverTableNames
 
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

QueryPlan.MarkerNode

public QueryPlan.MarkerNode(QueryPlanNode child,
                            java.lang.String mark_name)
Constructor.

Method Detail

evaluate

public Table evaluate(QueryContext context)
Description copied from interface: QueryPlanNode
Evaluates the node and returns the result as a Table. The VariableResolver resolves any outer variables


clone

public java.lang.Object clone()
                       throws java.lang.CloneNotSupportedException
Description copied from class: QueryPlan.SingleQueryPlanNode
Deep clone.

Specified by:
clone in interface QueryPlanNode
Overrides:
clone in class QueryPlan.SingleQueryPlanNode
Throws:
java.lang.CloneNotSupportedException

titleString

public java.lang.String titleString()
Overrides:
titleString in class QueryPlan.SingleQueryPlanNode