com.simba.dsi.ext.aetree
Class AESelect

java.lang.Object
  extended by com.simba.dsi.CppClassWrapper
      extended by com.simba.dsi.ext.aetree.AENode
          extended by com.simba.dsi.ext.aetree.AEQueryOperation
              extended by com.simba.dsi.ext.aetree.AERelationalExpr
                  extended by com.simba.dsi.ext.aetree.AEUnaryRelationalExpr
                      extended by com.simba.dsi.ext.aetree.AESelect

public final class AESelect
extends AEUnaryRelationalExpr

This class models the standard "selection" relational operation: SIGMA_(c)(R), where c is the selection condition and R is the relation to operate on.

AESelect models a simple SELECT(*)-FROM-WHERE query that does not involve any table joins. For example, the following SQL query can be translated to an AESelect operation directly,

 SELECT * FROM T WHERE cond
 
It is apparent that a SELECT operation only affects the set of rows returned. All columns of a row is returned if it satisfies the selection criterion.

An AESelect operation does not change the metadata of the relational expression that it operates on.


Constructor Summary
AESelect(long objRef)
          Constructor.
 
Method Summary
 AEBooleanExpr getSelectCond()
          Retrieves the select condition (AKA: filter).
 
Methods inherited from class com.simba.dsi.ext.aetree.AEUnaryRelationalExpr
getOperand
 
Methods inherited from class com.simba.dsi.ext.aetree.AERelationalExpr
isNamed
 
Methods inherited from class com.simba.dsi.ext.aetree.AEQueryOperation
getColumn, getColumnCount
 
Methods inherited from class com.simba.dsi.ext.aetree.AENode
getChild, getChildCount, getNodeType
 
Methods inherited from class com.simba.dsi.CppClassWrapper
getObjRef
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

AESelect

public AESelect(long objRef)
Constructor.

Parameters:
objRef - The corresponding C++ object reference.
Method Detail

getSelectCond

public AEBooleanExpr getSelectCond()
Retrieves the select condition (AKA: filter).

Returns:
The select condition.


Copyright © 2006-2014 Simba Technologies Incorporated. All Rights Reserved.