com.mckoi.database
Class QueryPlan.SingleRowTableNode

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

public static class QueryPlan.SingleRowTableNode
extends java.lang.Object
implements QueryPlanNode

A node for creating a table with a single row. This table is useful for queries that have no underlying row. For example, a pure functional table expression.

See Also:
Serialized Form

Constructor Summary
QueryPlan.SingleRowTableNode()
           
 
Method Summary
 java.lang.Object clone()
          Deep clones this query plan.
 void debugString(int level, java.lang.StringBuffer buf)
          Writes a textural representation of the node to the StringBuffer at the given indent level.
 java.util.ArrayList discoverCorrelatedVariables(int level, java.util.ArrayList list)
          Discovers all the correlated variables in the plan (and plan children) that reference a particular layer.
 java.util.ArrayList discoverTableNames(java.util.ArrayList list)
          Discovers a list of TableName that represent the sources that this query requires to complete itself.
 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
 

Constructor Detail

QueryPlan.SingleRowTableNode

public QueryPlan.SingleRowTableNode()
Method Detail

discoverTableNames

public java.util.ArrayList discoverTableNames(java.util.ArrayList list)
Description copied from interface: QueryPlanNode
Discovers a list of TableName that represent the sources that this query requires to complete itself. For example, if this is a query plan of two joined table, the fully resolved names of both tables are returned.

The resultant list will not contain the same table name more than once. The resultant list contains TableName objects.

NOTE, if a table is aliased, the unaliased name is returned.

Specified by:
discoverTableNames in interface QueryPlanNode

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

Specified by:
evaluate in interface QueryPlanNode

discoverCorrelatedVariables

public java.util.ArrayList discoverCorrelatedVariables(int level,
                                                       java.util.ArrayList list)
Description copied from interface: QueryPlanNode
Discovers all the correlated variables in the plan (and plan children) that reference a particular layer. For example, if we wanted to find all the CorrelatedVariable objects that reference the current layer, we would typically call 'discoverCorrelatedVariables(0, new ArrayList())'

Specified by:
discoverCorrelatedVariables in interface QueryPlanNode

clone

public java.lang.Object clone()
                       throws java.lang.CloneNotSupportedException
Description copied from interface: QueryPlanNode
Deep clones this query plan.

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

titleString

public java.lang.String titleString()

debugString

public void debugString(int level,
                        java.lang.StringBuffer buf)
Description copied from interface: QueryPlanNode
Writes a textural representation of the node to the StringBuffer at the given indent level.

Specified by:
debugString in interface QueryPlanNode