/* // $Id: //guest/julian_hyde/saffron/src/main/saffron/rel/NestedLoopJoinRule.java#2 $ // Saffron preprocessor and data engine // Copyright (C) 2002 Julian Hyde <julian.hyde@mail.com> // // This library is free software; you can redistribute it and/or // modify it under the terms of the GNU Library General Public // License as published by the Free Software Foundation; either // version 2 of the License, or (at your option) any later version. // // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU // Library General Public License for more details. // // You should have received a copy of the GNU Library General Public // License along with this library; if not, write to the // Free Software Foundation, Inc., 59 Temple Place - Suite 330, // Boston, MA 02111-1307, USA. // // See the COPYING file located in the top-level-directory of // the archive of this library for complete text of license. */ package saffron.rel; import saffron.opt.CallingConvention; import saffron.opt.Operand; import saffron.opt.RuleCall; import saffron.opt.SingleConventionRule; /** * Rule to translate a {@link Join} into a {@link * saffron.rel.java.JavaNestedLoopJoin}. It does so by calling {@link * Join#changeConvention}. **/ public class NestedLoopJoinRule extends SingleConventionRule { public NestedLoopJoinRule(int convention) { super( new Operand(Join.class, null), convention); } public void onMatch(RuleCall call) { Join join = (Join) call.rels[0]; if (join.getClass() == Join.class) { // We can translate a Join into an JavaNestedLoopJoin, but if // we allow sub-types, we end up translating an // JavaNestedLoopJoin into a copy of itself, forever. Rel converted = join; if (convention != CallingConvention.NONE) { converted = join.changeConvention(planner, convention); } if (converted != null) { call.transformTo(converted); } } } } // End NestedLoopJoinRule.java
# | Change | User | Description | Committed | |
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#2 | 1801 | Julian Hyde |
saffron: add ObjectSchema; rules can now be matched more than once; started to implement correlations in queries in from list. |
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#1 | 1467 | Julian Hyde |
saffron: First saffron check-in; incorporate my changes to openjava. |