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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN""http://www.w3.org/TR/REC-html40/loose.dtd"><!--NewPage--><HTML><HEAD><!-- Generated by javadoc on Wed Jan 15 11:28:12 CET 2003 --><TITLE>DbFalseExpr</TITLE><META NAME="keywords" CONTENT="javatools.db.DbFalseExpr,DbFalseExpr class"><LINK REL ="stylesheet" TYPE="text/css" HREF="../../stylesheet.css" TITLE="Style"></HEAD><SCRIPT>function asd(){parent.document.title="DbFalseExpr";}</SCRIPT><BODY BGCOLOR="white" onload="asd();"><!-- ========== START OF NAVBAR ========== --><A NAME="navbar_top"><!-- --></A><TABLE BORDER="0" WIDTH="100%" CELLPADDING="1" CELLSPACING="0"><TR><TD COLSPAN=3 BGCOLOR="#EEEEFF" CLASS="NavBarCell1"><A NAME="navbar_top_firstrow"><!-- --></A><TABLE BORDER="0" CELLPADDING="0" CELLSPACING="3"> <TR ALIGN="center" VALIGN="top"> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../overview-summary.html"><FONT CLASS="NavBarFont1"><B>Overview</B></FONT></A> </TD> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-summary.html"><FONT CLASS="NavBarFont1"><B>Package</B></FONT></A> </TD> <TD BGCOLOR="#FFFFFF" CLASS="NavBarCell1Rev"> <FONT CLASS="NavBarFont1Rev"><B>Class</B></FONT> </TD> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-tree.html"><FONT CLASS="NavBarFont1"><B>Tree</B></FONT></A> </TD> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../deprecated-list.html"><FONT CLASS="NavBarFont1"><B>Deprecated</B></FONT></A> </TD> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../index-all.html"><FONT CLASS="NavBarFont1"><B>Index</B></FONT></A> </TD> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../help-doc.html"><FONT CLASS="NavBarFont1"><B>Help</B></FONT></A> </TD> </TR></TABLE></TD><TD ALIGN="right" VALIGN="top" ROWSPAN=3><EM></EM></TD></TR><TR><TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2"> <A HREF="../../javatools/db/DbExprFuncDef.html"><B>PREV CLASS</B></A> <A HREF="../../javatools/db/DbFixedAbstractTable.html"><B>NEXT CLASS</B></A></FONT></TD><TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2"> <A HREF="../../index.html" TARGET="_top"><B>FRAMES</B></A> <A HREF="DbFalseExpr.html" TARGET="_top"><B>NO FRAMES</B></A> <SCRIPT> <!-- if(window==top) { document.writeln('<A HREF="../../allclasses-noframe.html" TARGET=""><B>All Classes</B></A>'); } //--></SCRIPT><NOSCRIPT><A HREF="../../allclasses-noframe.html" TARGET=""><B>All Classes</B></A></NOSCRIPT></FONT></TD></TR><TR><TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2"> SUMMARY: NESTED | FIELD | <A HREF="#constructor_summary">CONSTR</A> | <A HREF="#methods_inherited_from_class_javatools.db.DbCriterion">METHOD</A></FONT></TD><TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2">DETAIL: FIELD | <A HREF="#constructor_detail">CONSTR</A> | METHOD</FONT></TD></TR></TABLE><!-- =========== END OF NAVBAR =========== --><HR><!-- ======== START OF CLASS DATA ======== --><H2><FONT SIZE="-1">javatools.db</FONT><BR>Class DbFalseExpr</H2><PRE>java.lang.Object | +--<A HREF="../../javatools/db/DbExpr.html">javatools.db.DbExpr</A> | +--<A HREF="../../javatools/db/DbCriterion.html">javatools.db.DbCriterion</A> | +--<B>javatools.db.DbFalseExpr</B></PRE><DL><DT><B>All Implemented Interfaces:</B> <DD><A HREF="../../javatools/db/DbTableUser.html">DbTableUser</A></DD></DL><HR><DL><DT>public class <B>DbFalseExpr</B><DT>extends <A HREF="../../javatools/db/DbCriterion.html">DbCriterion</A></DL><P>An expression that always evaluates to false. If not optimised away by DbTrueExpr, it will probably result in "0 = 1" in the SQL. <P> The use of false expressions makes it very convenient for dynamically generated queries... <PRE> DbExpr e = db.falseExpr(); if (name != null) { e = e.or(table.getColumn("NAME")).equals(name)); } if (age != null) { e = e.or(table.getColumn("AGE")).equals(age)); } </PRE> This gets converted to... <PRE> (0 = 1) OR ( NAME = ? ) OR ( AGE = ? ) </PRE> and then DbOrExpr optimises this to... <PRE> ( NAME = ? ) OR ( AGE = ? ) </PRE><P><P><DL><DT><B>See Also:</B><DD><A HREF="../../javatools/db/DbOrExpr.html"><CODE>DbOrExpr</CODE></A></DL><HR><P><!-- ======== NESTED CLASS SUMMARY ======== --><!-- =========== FIELD SUMMARY =========== --><!-- ======== CONSTRUCTOR SUMMARY ======== --><A NAME="constructor_summary"><!-- --></A><TABLE BORDER="1" CELLPADDING="3" CELLSPACING="0" WIDTH="100%"><TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"><TD COLSPAN=2><FONT SIZE="+2"><B>Constructor Summary</B></FONT></TD></TR><TR BGCOLOR="white" CLASS="TableRowColor"><TD><CODE><B><A HREF="../../javatools/db/DbFalseExpr.html#DbFalseExpr(javatools.db.DbDatabase)">DbFalseExpr</A></B>(<A HREF="../../javatools/db/DbDatabase.html">DbDatabase</A> db)</CODE><BR> Builds a new false expression.</TD></TR></TABLE> <!-- ========== METHOD SUMMARY =========== --><A NAME="methods_inherited_from_class_javatools.db.DbCriterion"><!-- --></A><TABLE BORDER="1" CELLPADDING="3" CELLSPACING="0" WIDTH="100%"><TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor"><TD><B>Methods inherited from class javatools.db.<A HREF="../../javatools/db/DbCriterion.html">DbCriterion</A></B></TD></TR><TR BGCOLOR="white" CLASS="TableRowColor"><TD><CODE><A HREF="../../javatools/db/DbCriterion.html#getQueryString()">getQueryString</A>, <A HREF="../../javatools/db/DbCriterion.html#setSqlValues(java.sql.PreparedStatement, int)">setSqlValues</A>, <A HREF="../../javatools/db/DbCriterion.html#usesTables(java.util.Set)">usesTables</A></CODE></TD></TR></TABLE> <A NAME="methods_inherited_from_class_javatools.db.DbExpr"><!-- --></A><TABLE BORDER="1" CELLPADDING="3" CELLSPACING="0" WIDTH="100%"><TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor"><TD><B>Methods inherited from class javatools.db.<A HREF="../../javatools/db/DbExpr.html">DbExpr</A></B></TD></TR><TR BGCOLOR="white" CLASS="TableRowColor"><TD><CODE><A HREF="../../javatools/db/DbExpr.html#and(javatools.db.DbExpr)">and</A>, <A HREF="../../javatools/db/DbExpr.html#containsAllStrings(java.util.List)">containsAllStrings</A>, <A HREF="../../javatools/db/DbExpr.html#containsAllStrings(java.lang.String[])">containsAllStrings</A>, <A HREF="../../javatools/db/DbExpr.html#count()">count</A>, <A HREF="../../javatools/db/DbExpr.html#dateTrunc()">dateTrunc</A>, <A HREF="../../javatools/db/DbExpr.html#equal(java.lang.Object)">equal</A>, <A HREF="../../javatools/db/DbExpr.html#greaterThan(java.lang.Object)">greaterThan</A>, <A HREF="../../javatools/db/DbExpr.html#greaterThanOrEqual(java.lang.Object)">greaterThanOrEqual</A>, <A HREF="../../javatools/db/DbExpr.html#in(java.util.Collection)">in</A>, <A HREF="../../javatools/db/DbExpr.html#in(java.lang.Object)">in</A>, <A HREF="../../javatools/db/DbExpr.html#isNotNull()">isNotNull</A>, <A HREF="../../javatools/db/DbExpr.html#isNull()">isNull</A>, <A HREF="../../javatools/db/DbExpr.html#lessThan(java.lang.Object)">lessThan</A>, <A HREF="../../javatools/db/DbExpr.html#lessThanOrEqual(java.lang.Object)">lessThanOrEqual</A>, <A HREF="../../javatools/db/DbExpr.html#like(java.lang.Object)">like</A>, <A HREF="../../javatools/db/DbExpr.html#lower()">lower</A>, <A HREF="../../javatools/db/DbExpr.html#max()">max</A>, <A HREF="../../javatools/db/DbExpr.html#min()">min</A>, <A HREF="../../javatools/db/DbExpr.html#notEqual(java.lang.Object)">notEqual</A>, <A HREF="../../javatools/db/DbExpr.html#notIn(java.util.Collection)">notIn</A>, <A HREF="../../javatools/db/DbExpr.html#notIn(java.lang.Object)">notIn</A>, <A HREF="../../javatools/db/DbExpr.html#or(javatools.db.DbExpr)">or</A>, <A HREF="../../javatools/db/DbExpr.html#upper()">upper</A>, <A HREF="../../javatools/db/DbExpr.html#usesTables(java.util.Set, java.lang.Object)">usesTables</A></CODE></TD></TR></TABLE> <A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A><TABLE BORDER="1" CELLPADDING="3" CELLSPACING="0" WIDTH="100%"><TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor"><TD><B>Methods inherited from class java.lang.Object</B></TD></TR><TR BGCOLOR="white" CLASS="TableRowColor"><TD><CODE>clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait</CODE></TD></TR></TABLE> <P><!-- ============ FIELD DETAIL =========== --><!-- ========= CONSTRUCTOR DETAIL ======== --><A NAME="constructor_detail"><!-- --></A><TABLE BORDER="1" CELLPADDING="3" CELLSPACING="0" WIDTH="100%"><TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"><TD COLSPAN=1><FONT SIZE="+2"><B>Constructor Detail</B></FONT></TD></TR></TABLE><A NAME="DbFalseExpr(javatools.db.DbDatabase)"><!-- --></A><H3>DbFalseExpr</H3><PRE>public <B>DbFalseExpr</B>(<A HREF="../../javatools/db/DbDatabase.html">DbDatabase</A> db)</PRE><DL><DD>Builds a new false expression.<P><DT><B>Parameters:</B><DD><CODE>db</CODE> - The database that will be used.</DL><!-- ============ METHOD DETAIL ========== --><!-- ========= END OF CLASS DATA ========= --><HR><!-- ========== START OF NAVBAR ========== --><A NAME="navbar_bottom"><!-- --></A><TABLE BORDER="0" WIDTH="100%" CELLPADDING="1" CELLSPACING="0"><TR><TD COLSPAN=3 BGCOLOR="#EEEEFF" CLASS="NavBarCell1"><A NAME="navbar_bottom_firstrow"><!-- --></A><TABLE BORDER="0" CELLPADDING="0" CELLSPACING="3"> <TR ALIGN="center" VALIGN="top"> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../overview-summary.html"><FONT CLASS="NavBarFont1"><B>Overview</B></FONT></A> </TD> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-summary.html"><FONT CLASS="NavBarFont1"><B>Package</B></FONT></A> </TD> <TD BGCOLOR="#FFFFFF" CLASS="NavBarCell1Rev"> <FONT CLASS="NavBarFont1Rev"><B>Class</B></FONT> </TD> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-tree.html"><FONT CLASS="NavBarFont1"><B>Tree</B></FONT></A> </TD> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../deprecated-list.html"><FONT CLASS="NavBarFont1"><B>Deprecated</B></FONT></A> </TD> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../index-all.html"><FONT CLASS="NavBarFont1"><B>Index</B></FONT></A> </TD> <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../help-doc.html"><FONT CLASS="NavBarFont1"><B>Help</B></FONT></A> </TD> </TR></TABLE></TD><TD ALIGN="right" VALIGN="top" ROWSPAN=3><EM></EM></TD></TR><TR><TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2"> <A HREF="../../javatools/db/DbExprFuncDef.html"><B>PREV CLASS</B></A> <A HREF="../../javatools/db/DbFixedAbstractTable.html"><B>NEXT 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