com.mckoi.database
Class QueryPlan.LeftOuterJoinNode
java.lang.Object
com.mckoi.database.QueryPlan.SingleQueryPlanNode
com.mckoi.database.QueryPlan.LeftOuterJoinNode
- All Implemented Interfaces:
- QueryPlanNode, java.io.Serializable, java.lang.Cloneable
- Enclosing class:
- QueryPlan
public static class QueryPlan.LeftOuterJoinNode
- extends QueryPlan.SingleQueryPlanNode
A branch node for a left outer join. Using this node is a little non-
intuitive. This node will only work when used in conjuction with
MarkerNode.
To use - first the complete left table in the join must be marked with a
name. Then the ON expression is evaluated to a single plan node. Then
this plan node must be added to result in a left outer join. A tree for
a left outer join may look as follows;
LeftOuterJoinNode
|
Join a = b
/ \
Marker GetTable T2
|
GetTable T1
- See Also:
- Serialized Form
Methods inherited from class java.lang.Object |
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
QueryPlan.LeftOuterJoinNode
public QueryPlan.LeftOuterJoinNode(QueryPlanNode child,
java.lang.String complete_mark_name)
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.SingleQueryPlanNode