Apache Derby 10.6

org.apache.derby.vti
Class Restriction

java.lang.Object
  extended by org.apache.derby.vti.Restriction
All Implemented Interfaces:
java.io.Serializable
Direct Known Subclasses:
Restriction.AND, Restriction.ColumnQualifier, Restriction.OR

public abstract class Restriction
extends java.lang.Object
implements java.io.Serializable

An expression to be pushed into a Table Function so that the Table Function can short-circuit its processing and return fewer rows. A restriction is represented as a binary tree. The non-leaf nodes are ANDs and ORs. The leaf nodes are ColumnQualifiers. A ColumnQualifier is a simple expression comparing a constant value to a column in the Table Function.

See Also:
Serialized Form

Nested Class Summary
static class Restriction.AND
          An AND of two Restrictions
static class Restriction.ColumnQualifier
           A simple comparison of a column to a constant value.
static class Restriction.OR
          An OR of two Restrictions
 
Constructor Summary
Restriction()
           
 
Method Summary
protected  java.lang.String doubleQuote(java.lang.String raw)
          Utility method to double quote a string
protected  java.lang.String parenthesize(java.lang.String raw)
          Utility method to parenthesize an expression
abstract  java.lang.String toSQL()
          Turn this Restriction into a string suitable for use in a WHERE clause.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Restriction

public Restriction()
Method Detail

toSQL

public abstract java.lang.String toSQL()
Turn this Restriction into a string suitable for use in a WHERE clause.


doubleQuote

protected java.lang.String doubleQuote(java.lang.String raw)
Utility method to double quote a string


parenthesize

protected java.lang.String parenthesize(java.lang.String raw)
Utility method to parenthesize an expression


Built on Mon 2010-04-26 13:23:26-0700, from revision 938214

Apache Derby 10.6 API Documentation - Copyright © 2004,2008 The Apache Software Foundation. All Rights Reserved.