com.mckoi.database.QueryPlan.FetchViewNode

All Implemented Interfaces:: QueryPlanNode, Serializable, Cloneable

Enclosing class:: QueryPlan

public static class QueryPlan.FetchViewNode extends Object implements QueryPlanNode

The node that fetches a view from the current connection. This is a tree node that has no children, however the child can be created by calling the 'createViewChildNode' method. This node can be removed from a plan tree by calling the 'createViewChildNode' method and substituting this node with the returned child. For a planner that normalizes and optimizes plan trees, this is a useful feature.

See Also:

Constructor Summary

Constructors

Constructor

Description

FetchViewNode(TableName table_name, TableName aliased_as)
Method Summary

Modifier and Type

Method

Description

Object

clone()

Deep clones this query plan.

QueryPlanNode

createViewChildNode(QueryContext context)

Returns the QueryPlanNode that resolves to the view.

void

debugString(int level, StringBuffer buf)

Writes a textural representation of the node to the StringBuffer at the given indent level.

ArrayList

discoverCorrelatedVariables(int level, ArrayList list)

Discovers all the correlated variables in the plan (and plan children) that reference a particular layer.

ArrayList

discoverTableNames(ArrayList list)

Adds the table name to the list if it's not already in there.

Table

evaluate(QueryContext context)

Evaluates the node and returns the result as a Table.

String

titleString()

Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details
- FetchViewNode
  
  public FetchViewNode(TableName table_name, TableName aliased_as)
Method Details
- createViewChildNode
  
  public QueryPlanNode createViewChildNode(QueryContext context)
  
  Returns the QueryPlanNode that resolves to the view. This looks up the query plan in the context given.
- discoverTableNames
  
  public ArrayList discoverTableNames(ArrayList list)
  
  Adds the table name to the list if it's not already in there.
  
  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 ArrayList discoverCorrelatedVariables(int level, 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 Object clone() throws CloneNotSupportedException
  
  Description copied from interface: QueryPlanNode
  
  Deep clones this query plan.
  
  Specified by:
  
  clone in interface QueryPlanNode
  
  Overrides:
  
  clone in class Object
  
  Throws:
  
  CloneNotSupportedException
- titleString
  
  public String titleString()
- debugString
  
  public void debugString(int level, 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

Class QueryPlan.FetchViewNode

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Details

FetchViewNode

Method Details

createViewChildNode

discoverTableNames

evaluate

discoverCorrelatedVariables

clone

titleString

debugString