algebraTree
Class Update

java.lang.Object
  |
  +--algebraTree.Update
Direct Known Subclasses:
DataUpdate, SchemaUpdate

public abstract class Update
extends java.lang.Object

Objects of this class represent updates for a SchemaSQL wrapper. SchemaSQL updates include data updates as well as schema updates. Data updates can be add-tuple, delete-tuple, or update-tuple (with arbitrary changes in the data). A data update is represented by a "before-after" pair. If "before" is empty, we have an add, if "after" is empty, we have a delete, if both are not-null, we have an update. Schema changes are {add|del|ren}-{att|rel} such that the attribute/relation must be identified and the type of update too. These two updates classes are two subclasses of this one.


Field Summary
 java.lang.String relation
          the table name which this update concerns.
 
Constructor Summary
Update()
           
 
Methods inherited from class java.lang.Object
, clone, equals, finalize, getClass, hashCode, notify, notifyAll, registerNatives, toString, wait, wait, wait
 

Field Detail

relation

public java.lang.String relation
the table name which this update concerns. Must be valid
Constructor Detail

Update

public Update()