Apache Derby 10.6

Class Restriction

  extended by org.apache.derby.vti.Restriction
All Implemented Interfaces:
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
Method Summary
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


public Restriction()
Method Detail


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


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

Built on Tue 2010-09-21 16:20:41-0700, from revision 999685

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