Apache
/
openjpa
mirror of https://github.com/apache/openjpa.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Optimize queries of the form "select e from ... where e.rel.id = :x" to not join 

across "rel" for std fk->pk joins. 



git-svn-id: https://svn.apache.org/repos/asf/incubator/openjpa/trunk@462646 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
A. Abram White 2006-10-11 00:16:53 +00:00
parent f27898f280
commit 6937856e2b
4 changed files with 221 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

72
openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/kernel/exps/PCPath.java
View File

@ -27,6 +27,7 @@ import org.apache.openjpa.jdbc.meta.ClassMapping;
import org.apache.openjpa.jdbc.meta.FieldMapping;
import org.apache.openjpa.jdbc.meta.ValueMapping;
import org.apache.openjpa.jdbc.schema.Column;
import org.apache.openjpa.jdbc.schema.ForeignKey;
import org.apache.openjpa.jdbc.schema.Schemas;
import org.apache.openjpa.jdbc.sql.Joins;
import org.apache.openjpa.jdbc.sql.Result;
@ -352,6 +353,7 @@ class PCPath
Action action;
Variable var;
Iterator itr = (_actions == null) ? null : _actions.iterator();
FieldMapping field;
while (itr != null && itr.hasNext()) {
action = (Action) itr.next();
@ -369,8 +371,18 @@ class PCPath
rel.getTable());
} else {
// move past the previous field, if any
if (pstate.field != null)
field = (FieldMapping) action.data;
if (pstate.field != null) {
// if this is the second-to-last field and the last is
// the related field this field joins to, no need to
// traverse: just use this field's fk columns
if (!itr.hasNext() && (flags & JOIN_REL) == 0
&& isJoinedField(pstate.field, key, field)) {
pstate.cmpfield = field;
break;
}
rel = traverseField(pstate, key, forceOuter, false);
}
// mark if the next traversal should go through
// the key rather than value
@ -378,7 +390,7 @@ class PCPath
forceOuter |= action.op == Action.GET_OUTER;
// get mapping for the current field
pstate.field = (FieldMapping) action.data;
pstate.field = field;
owner = pstate.field.getDefiningMapping();
if (pstate.field.getManagement()
!= FieldMapping.MANAGE_PERSISTENT)
@ -420,15 +432,50 @@ class PCPath
return pstate;
}
/**
* Return whether the given source field joins to the given target field.
*/
private static boolean isJoinedField(FieldMapping src, boolean key,
FieldMapping target) {
ValueMapping vm;
switch (src.getTypeCode()) {
case JavaTypes.ARRAY:
case JavaTypes.COLLECTION:
vm = src.getElementMapping();
break;
case JavaTypes.MAP:
vm = (key) ? src.getKeyMapping() : src.getElementMapping();
break;
default:
vm = src;
}
if (vm.getJoinDirection() != ValueMapping.JOIN_FORWARD)
return false;
ForeignKey fk = vm.getForeignKey();
if (fk == null)
return false;
// foreign key must join to target columns
Column[] rels = fk.getColumns();
Column[] pks = target.getColumns();
if (rels.length != pks.length)
return false;
for (int i = 0; i < rels.length; i++)
if (fk.getPrimaryKeyColumn(rels[i]) != pks[i])
return false;
return true;
}
/**
* Expression state.
*/
private static class PathExpState
extends ExpState {
private FieldMapping field = null;
private Column[] cols = null;
private boolean joinedRel = false;
public FieldMapping field = null;
public FieldMapping cmpfield = null;
public Column[] cols = null;
public boolean joinedRel = false;
public PathExpState(Joins joins) {
super(joins);
@ -483,15 +530,16 @@ class PCPath
public Object toDataStoreValue(Select sel, ExpContext ctx, ExpState state,
Object val) {
PathExpState pstate = (PathExpState) state;
if (pstate.field != null) {
FieldMapping field = (pstate.cmpfield != null) ? pstate.cmpfield
: pstate.field;
if (field != null) {
if (_key)
return pstate.field.toKeyDataStoreValue(val, ctx.store);
if (pstate.field.getElement().getDeclaredTypeCode()
!= JavaTypes.OBJECT)
return pstate.field.toDataStoreValue(val, ctx.store);
return field.toKeyDataStoreValue(val, ctx.store);
if (field.getElement().getDeclaredTypeCode() != JavaTypes.OBJECT)
return field.toDataStoreValue(val, ctx.store);
val = pstate.field.getExternalValue(val, ctx.store.getContext());
return pstate.field.toDataStoreValue(val, ctx.store);
val = field.getExternalValue(val, ctx.store.getContext());
return field.toDataStoreValue(val, ctx.store);
}
return _class.toDataStoreValue(val, _class.getPrimaryKeyColumns(),
ctx.store);

2
openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/meta/strats/RelationStrategies.java
View File

@ -74,7 +74,7 @@ public class RelationStrategies {
public static Object toDataStoreValue(ValueMapping vm, Object val,
JDBCStore store) {
ClassMapping rel;
if (val == null || val.getClass() == vm.getType())
if (val == null || val.getClass() == vm.getType())
rel = vm.getTypeMapping(); // common case
else
rel = vm.getMappingRepository().getMapping(val.getClass(),

59
openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/query/ManyOneEntity.java Executable file
View File

@ -0,0 +1,59 @@
/*
* Copyright 2006 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.openjpa.persistence.query;
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Version;
@Entity
public class ManyOneEntity {
@Id
@GeneratedValue
private long id;
private String name;
@ManyToOne(cascade=CascadeType.ALL)
private ManyOneEntity rel;
@Version
private Integer optLock;
public long getId() {
return id;
}
public ManyOneEntity getRel() {
return rel;
}
public void setRel(ManyOneEntity rel) {
this.rel = rel;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}

101
openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/query/TestQueryIdOfRelationDoesNotJoin.java Normal file
View File

@ -0,0 +1,101 @@
/*
* Copyright 2006 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.openjpa.persistence.query;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;
import junit.framework.TestCase;
import junit.textui.TestRunner;
/**
* Test that querying the id of a related many-one (or one-one) does not create
* a join across the tables.
*
* @author Abe White
*/
public class TestQueryIdOfRelationDoesNotJoin
extends TestCase {
private EntityManagerFactory emf;
private long e3Id;
public void setUp() {
Map props = new HashMap();
props.put("openjpa.MetaDataFactory", "jpa(Types="
+ ManyOneEntity.class.getName() + ")");
emf = Persistence.createEntityManagerFactory("test", props);
ManyOneEntity e1 = new ManyOneEntity();
e1.setName("e1");
ManyOneEntity e2 = new ManyOneEntity();
e2.setName("e2");
ManyOneEntity e3 = new ManyOneEntity();
e3.setName("e3");
e1.setRel(e3);
e2.setRel(e1);
EntityManager em = emf.createEntityManager();
em.getTransaction().begin();
em.persist(e1);
em.getTransaction().commit();
e3Id = e3.getId();
// we intentionally create an orphaned reference on e1.rel
em.getTransaction().begin();
em.remove(e3);
em.getTransaction().commit();
em.close();
}
public void tearDown() {
if (emf == null)
return;
try {
EntityManager em = emf.createEntityManager();
em.getTransaction().begin();
em.createQuery("delete from ManyOneEntity").executeUpdate();
em.getTransaction().commit();
em.close();
emf.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public void testQuery() {
EntityManager em = emf.createEntityManager();
Query q = em.createQuery("select e from ManyOneEntity e "
+ "where e.rel.id = :id").setParameter("id", e3Id);
List res = q.getResultList();
assertEquals(1, res.size());
ManyOneEntity e = (ManyOneEntity) res.get(0);
assertEquals("e1", e.getName());
assertNull(e.getRel());
em.close();
}
public static void main(String[] args) {
TestRunner.run(TestQueryIdOfRelationDoesNotJoin.class);
}
}