Package com.mckoi.database

Class QueryPlan.LogicalUnionNode

java.lang.Object

com.mckoi.database.QueryPlan.BranchQueryPlanNode

com.mckoi.database.QueryPlan.LogicalUnionNode

All Implemented Interfaces:

QueryPlanNode, java.io.Serializable, java.lang.Cloneable

Enclosing class:

QueryPlan

public static class QueryPlan.LogicalUnionNode
extends QueryPlan.BranchQueryPlanNode

A branch node for a logical union of two tables of identical types. This branch can only work if the left and right children have exactly the same ancestor tables. If the ancestor tables are different it will fail. This node is used for logical OR.

This union does not include duplicated rows.

See Also:

Serialized Form

Field Summary

Fields inherited from class com.mckoi.database.QueryPlan.BranchQueryPlanNode

left, right

Constructor Summary

Constructors

Constructor	Description
LogicalUnionNode(QueryPlanNode left, QueryPlanNode right)

Method Summary

Modifier and Type	Method	Description
Table	evaluate(QueryContext context)	Evaluates the node and returns the result as a Table.
java.lang.String	titleString()

Methods inherited from class java.lang.Object

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

Methods inherited from class com.mckoi.database.QueryPlan.BranchQueryPlanNode

clone, debugString, discoverCorrelatedVariables, discoverTableNames, left, right

Constructor Detail

LogicalUnionNode

public LogicalUnionNode(QueryPlanNode left,
                        QueryPlanNode right)

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

titleString

public java.lang.String titleString()

Overrides:

titleString in class QueryPlan.BranchQueryPlanNode