HHH-3972 - Adding FETCH FIRST and OFFSET support to DerbyDialect

git-svn-id: https://svn.jboss.org/repos/hibernate/core/trunk@17867 1b8cb986-b30d-0410-93ca-fae66ebed9b2
This commit is contained in:
Steve Ebersole 2009-10-28 15:49:36 +00:00
parent a1e8d7cb0d
commit 9909f9ce72
2 changed files with 190 additions and 2 deletions

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@ -27,6 +27,7 @@ package org.hibernate.dialect;
import org.hibernate.Hibernate;
import org.hibernate.QueryException;
import org.hibernate.HibernateException;
import org.hibernate.util.ReflectHelper;
import org.hibernate.engine.Mapping;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.type.Type;
@ -39,6 +40,10 @@ import org.hibernate.sql.DerbyCaseFragment;
import java.util.List;
import java.util.ArrayList;
import java.lang.reflect.Method;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Hibernate Dialect for Cloudscape 10 - aka Derby. This implements both an
@ -49,13 +54,39 @@ import java.util.ArrayList;
* @author Simon Johnston
*/
public class DerbyDialect extends DB2Dialect {
private static final Logger log = LoggerFactory.getLogger( DerbyDialect.class );
private int driverVersionMajor;
private int driverVersionMinor;
public DerbyDialect() {
super();
registerFunction( "concat", new DerbyConcatFunction() );
registerFunction( "trim", new DerbyTrimFunctionEmulation() );
determineDriverVersion();
}
/*package*/ void determineDriverVersion() {
try {
// locate the derby sysinfo class and query its version info
final Class sysinfoClass = ReflectHelper.classForName( "org.apache.derby.tools.sysinfo", this.getClass() );
final Method majorVersionGetter = sysinfoClass.getMethod( "getMajorVersion", ReflectHelper.NO_PARAM_SIGNATURE );
final Method minorVersionGetter = sysinfoClass.getMethod( "getMinorVersion", ReflectHelper.NO_PARAM_SIGNATURE );
driverVersionMajor = ( (Integer) majorVersionGetter.invoke( null, ReflectHelper.NO_PARAMS ) ).intValue();
driverVersionMinor = ( (Integer) minorVersionGetter.invoke( null, ReflectHelper.NO_PARAMS ) ).intValue();
}
catch ( Exception e ) {
log.warn( "Unable to load/access derby driver class sysinfo to check versions : " + e );
driverVersionMajor = -1;
driverVersionMinor = -1;
}
}
/*package*/ boolean isTenPointFiveReleaseOrNewer() {
return driverVersionMajor > 10 || ( driverVersionMajor == 10 && driverVersionMinor >= 5 );
}
/**
* This is different in Cloudscape to DB2.
*/
@ -83,11 +114,75 @@ public class DerbyDialect extends DB2Dialect {
}
public boolean supportsLimit() {
return false;
return isTenPointFiveReleaseOrNewer();
}
public boolean supportsLimitOffset() {
return false;
return isTenPointFiveReleaseOrNewer();
}
/**
* {@inheritDoc}
* <p/>
* From Derby 10.5 Docs:
* <pre>
* Query
* [ORDER BY clause]
* [result offset clause]
* [fetch first clause]
* [FOR UPDATE clause]
* [WITH {RR|RS|CS|UR}]
* </pre>
*/
public String getLimitString(String query, final int offset, final int limit) {
StringBuffer sb = new StringBuffer(query.length() + 50);
final String normalizedSelect = query.toLowerCase().trim();
final int forUpdateIndex = normalizedSelect.lastIndexOf( "for update") ;
if ( hasForUpdateClause( forUpdateIndex ) ) {
sb.append( query.substring( 0, forUpdateIndex-1 ) );
}
else if ( hasWithClause( normalizedSelect ) ) {
sb.append( query.substring( 0, getWithIndex( query ) - 1 ) );
}
else {
sb.append( query );
}
if ( offset == 0 ) {
sb.append( " fetch first " );
}
else {
sb.append( " offset " ).append( offset ).append( " rows fetch next " );
}
sb.append( limit ).append( " rows only" );
if ( hasForUpdateClause( forUpdateIndex ) ) {
sb.append(' ');
sb.append( query.substring( forUpdateIndex ) );
}
else if ( hasWithClause( normalizedSelect ) ) {
sb.append( ' ' ).append( query.substring( getWithIndex( query ) ) );
}
return sb.toString();
}
private boolean hasForUpdateClause(int forUpdateIndex) {
return forUpdateIndex >= 0;
}
private boolean hasWithClause(String normalizedSelect){
return normalizedSelect.startsWith( "with ", normalizedSelect.length()-7 );
}
private int getWithIndex(String querySelect) {
int i = querySelect.lastIndexOf( "with " );
if ( i < 0 ) {
i = querySelect.lastIndexOf( "WITH " );
}
return i;
}
public String getQuerySequencesString() {

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@ -0,0 +1,93 @@
/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2009 by Red Hat Inc and/or its affiliates or by
* third-party contributors as indicated by either @author tags or express
* copyright attribution statements applied by the authors. All
* third-party contributions are distributed under license by Red Hat Inc.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program 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 Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.hibernate.dialect;
import junit.framework.TestCase;
/**
* Testing of patched support for Derby limit and ofset queries; see HHH-3972
*
* @author Evan Leonard
*/
public class DerbyDialectTestCase extends TestCase {
private static class LocalDerbyDialect extends DerbyDialect {
protected boolean isTenPointFiveReleaseOrNewer() {
return true; // for test sake :)
}
}
public void testInsertLimitClause() {
final int limit = 50;
final String input = "select * from tablename t where t.cat = 5";
final String expected = "select * from tablename t where t.cat = 5 fetch first " + limit + " rows only";
final String actual = new LocalDerbyDialect().getLimitString( input, 0, limit );
assertEquals( expected, actual );
}
public void testInsertLimitWithOffsetClause() {
final int limit = 50;
final int offset = 200;
final String input = "select * from tablename t where t.cat = 5";
final String expected = "select * from tablename t where t.cat = 5 offset " + offset + " rows fetch next " + limit + " rows only";
final String actual = new LocalDerbyDialect().getLimitString( input, offset, limit );
assertEquals( expected, actual );
}
public void testInsertLimitWithForUpdateClause() {
final int limit = 50;
final int offset = 200;
final String input = "select c11 as col1, c12 as col2, c13 as col13 from t1 for update of c11, c13";
final String expected = "select c11 as col1, c12 as col2, c13 as col13 from t1 offset " + offset
+ " rows fetch next " + limit + " rows only for update of c11, c13";
final String actual = new LocalDerbyDialect().getLimitString( input, offset, limit );
assertEquals( expected, actual );
}
public void testInsertLimitWithWithClause() {
final int limit = 50;
final int offset = 200;
final String input = "select c11 as col1, c12 as col2, c13 as col13 from t1 where flight_id between 'AA1111' and 'AA1112' with rr";
final String expected = "select c11 as col1, c12 as col2, c13 as col13 from t1 where flight_id between 'AA1111' and 'AA1112' offset " + offset
+ " rows fetch next " + limit + " rows only with rr";
final String actual = new LocalDerbyDialect().getLimitString( input, offset, limit );
assertEquals( expected, actual );
}
public void testInsertLimitWithForUpdateAndWithClauses() {
final int limit = 50;
final int offset = 200;
final String input = "select c11 as col1, c12 as col2, c13 as col13 from t1 where flight_id between 'AA1111' and 'AA1112' for update of c11,c13 with rr";
final String expected = "select c11 as col1, c12 as col2, c13 as col13 from t1 where flight_id between 'AA1111' and 'AA1112' offset " + offset
+ " rows fetch next " + limit + " rows only for update of c11,c13 with rr";
final String actual = new LocalDerbyDialect().getLimitString( input, offset, limit );
assertEquals( expected, actual );
}
}