HHH-951 - Fix setMaxResults causes "ORA-00918: column ambiguously defined" exception on Oracle

hibernate-core/src/main/java/org/hibernate/hql/internal/ast/tree/SelectClause.java

@@ -31,6 +31,7 @@ public class SelectClause extends SelectExpressionList {
 	private boolean scalarSelect;
 
 	private List fromElementsForLoad = new ArrayList();
+	private List alreadyRenderedIdentifiers = new ArrayList();
 	//private Type[] sqlResultTypes;
 	private Type[] queryReturnTypes;
 	private String[][] columnNames;
@@ -224,6 +225,7 @@ public class SelectClause extends SelectExpressionList {
 							//sqlResultTypeList.add( type );
 							// Generate the select expression.
 							String text = fromElement.renderIdentifierSelect( size, k );
+							alreadyRenderedIdentifiers.add( text );
 							SelectExpressionImpl generatedExpr = (SelectExpressionImpl) appender.append(
 									SqlTokenTypes.SELECT_EXPR,
 									text,
@@ -355,6 +357,7 @@ public class SelectClause extends SelectExpressionList {
 		}
 	}
 
+	@Override
 	protected AST getFirstSelectExpression() {
 		AST n = getFirstChild();
 		// Skip 'DISTINCT' and 'ALL', so we return the first expression node.
@@ -450,7 +453,10 @@ public class SelectClause extends SelectExpressionList {
 				expr.setText( text );
 			}
 			else {
-				appender.append( SqlTokenTypes.SQL_TOKEN, text, false );
+				if (! alreadyRenderedIdentifiers.contains(text)) {
+					appender.append( SqlTokenTypes.SQL_TOKEN, text, false );
+					alreadyRenderedIdentifiers.add(text);
+				}
 			}
 		}
 	}

hibernate-core/src/test/java/org/hibernate/test/pagination/DataMetaPoint.java

@@ -0,0 +1,78 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.test.pagination;
+
+/**
+ * @author Piotr Findeisen <piotr.findeisen@gmail.com>
+ */
+public class DataMetaPoint {
+	private long id;
+	private DataPoint dataPoint;
+	private String meta;
+
+	/**
+	 * @return Returns the id.
+	 */
+	public long getId() {
+		return id;
+	}
+
+	/**
+	 * @param id
+	 *            The id to set.
+	 */
+	public void setId(long id) {
+		this.id = id;
+	}
+
+	public DataPoint getDataPoint() {
+		return dataPoint;
+	}
+
+	public void setDataPoint(DataPoint dataPoint) {
+		this.dataPoint = dataPoint;
+	}
+
+	public String getMeta() {
+		return meta;
+	}
+
+	public void setMeta(String meta) {
+		this.meta = meta;
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((dataPoint == null) ? 0 : dataPoint.hashCode());
+		result = prime * result + (int) (id ^ (id >>> 32));
+		result = prime * result + ((meta == null) ? 0 : meta.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		if (this == o) {
+			return true;
+		}
+		if (o == null || getClass() != o.getClass()) {
+			return false;
+		}
+
+		DataMetaPoint dataPoint = (DataMetaPoint) o;
+
+		if (meta != null ? !meta.equals(dataPoint.meta) : dataPoint.meta != null) {
+			return false;
+		}
+		if (dataPoint != null ? !dataPoint.equals(dataPoint.dataPoint) : dataPoint.dataPoint != null) {
+			return false;
+		}
+
+		return true;
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/pagination/DataPoint.hbm.xml

@@ -28,4 +28,13 @@
 		<property name="description"/>
 	</class>
 
+	<class name="DataMetaPoint"
+		dynamic-update="true">
+		<id name="id">
+			<generator class="increment"/>
+		</id>
+        <property name="meta" />
+        <many-to-one name="dataPoint" class="DataPoint" />
+	</class>
+
 </hibernate-mapping>

hibernate-core/src/test/java/org/hibernate/test/pagination/PaginationTest.java

@@ -7,21 +7,27 @@
 package org.hibernate.test.pagination;
 
 import java.math.BigDecimal;
+import java.util.Collections;
 import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import org.hibernate.Criteria;
 import org.hibernate.Query;
 import org.hibernate.SQLQuery;
 import org.hibernate.Session;
 import org.hibernate.criterion.Order;
-
+import org.hibernate.engine.query.spi.HQLQueryPlan;
 import org.hibernate.testing.DialectChecks;
 import org.hibernate.testing.RequiresDialectFeature;
+import org.hibernate.testing.TestForIssue;
 import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
 import org.junit.Test;
 
+import static java.lang.String.format;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 /**
  * @author Gavin King
@@ -101,6 +107,41 @@ public class PaginationTest extends BaseNonConfigCoreFunctionalTestCase {
 		cleanupTestData();
 	}
 
+	/**
+	 * @author Piotr Findeisen <piotr.findeisen@gmail.com>
+	 */
+	@Test
+	@TestForIssue( jiraKey = "HHH-951" )
+	@RequiresDialectFeature(
+			value = DialectChecks.SupportLimitCheck.class,
+			comment = "Dialect does not support limit"
+	)
+	public void testLimitWithExpreesionAndFetchJoin() {
+		Session session = openSession();
+		session.beginTransaction();
+
+		String hql = "SELECT b, 1 FROM DataMetaPoint b inner join fetch b.dataPoint dp";
+		session.createQuery(hql)
+				.setMaxResults(3)
+				// This should not fail
+				.list();
+
+		HQLQueryPlan queryPlan = new HQLQueryPlan(hql, false, Collections.EMPTY_MAP, sessionFactory());
+		String sqlQuery = queryPlan.getTranslators()[0]
+				.collectSqlStrings().get(0);
+
+		session.getTransaction().commit();
+		session.close();
+
+		Matcher matcher = Pattern.compile(
+				"(?is)\\b(?<column>\\w+\\.\\w+)\\s+as\\s+(?<alias>\\w+)\\b.*\\k<column>\\s+as\\s+\\k<alias>")
+				.matcher(sqlQuery);
+		if (matcher.find()) {
+			fail(format("Column %s mapped to alias %s twice in generated SQL: %s", matcher.group("column"),
+					matcher.group("alias"), sqlQuery));
+		}
+	}
+
 	@Test
 	@RequiresDialectFeature(
 			value = DialectChecks.SupportLimitAndOffsetCheck.class,