1 /* 2 * ModeShape (http://www.modeshape.org) 3 * See the COPYRIGHT.txt file distributed with this work for information 4 * regarding copyright ownership. Some portions may be licensed 5 * to Red Hat, Inc. under one or more contributor license agreements. 6 * See the AUTHORS.txt file in the distribution for a full listing of 7 * individual contributors. 8 * 9 * ModeShape is free software. Unless otherwise indicated, all code in ModeShape 10 * is licensed to you under the terms of the GNU Lesser General Public License as 11 * published by the Free Software Foundation; either version 2.1 of 12 * the License, or (at your option) any later version. 13 * 14 * ModeShape is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * Lesser General Public License for more details. 18 * 19 * You should have received a copy of the GNU Lesser General Public 20 * License along with this software; if not, write to the Free 21 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 22 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 23 */ 24 package org.modeshape.jcr.api.query.qom; 25 26 import javax.jcr.query.Query; 27 import javax.jcr.query.qom.QueryObjectModel; 28 import javax.jcr.query.qom.QueryObjectModelFactory; 29 30 /** 31 * A set query extension to the JCR query object model. 32 * <p> 33 * The JCR query object model describes the queries that can be evaluated by a JCR repository independent of any particular query 34 * language, such as SQL. JCR defines the {@link QueryObjectModel} interface as the primary representatino of this query object 35 * model, but this interface is not sufficient for certain queries, such as unions or intersections of other queries. This 36 * interface is an extension to the JCR API that mirrors the QueryObjectModel interface for set queries. 37 * </p> 38 * <p> 39 * A query consists of: 40 * <ul> 41 * <li>a source. When the query is evaluated, the source evaluates its selectors and the joins between them to produce a (possibly 42 * empty) set of node-tuples. This is a set of 1-tuples if the query has one selector (and therefore no joins), a set of 2-tuples 43 * if the query has two selectors (and therefore one join), a set of 3-tuples if the query has three selectors (two joins), and so 44 * forth.</li> 45 * <li>an optional constraint. When the query is evaluated, the constraint filters the set of node-tuples.</li> 46 * <li>a list of zero or more orderings. The orderings specify the order in which the node-tuples appear in the query results. The 47 * relative order of two node-tuples is determined by evaluating the specified orderings, in list order, until encountering an 48 * ordering for which one node-tuple precedes the other. If no orderings are specified, or if for none of the specified orderings 49 * does one node-tuple precede the other, then the relative order of the node-tuples is implementation determined (and may be 50 * arbitrary).</li> 51 * <li>a list of zero or more columns to include in the tabular view of the query results. If no columns are specified, the 52 * columns available in the tabular view are implementation determined, but minimally include, for each selector, a column for 53 * each single-valued non-residual property of the selector's node type.</li> 54 * </ul> 55 * <p> 56 * The query object model representation of a query is created by factory methods in the {@link QueryObjectModelFactory}. 57 * 58 * @see QueryObjectModel 59 */ 60 public interface SetQueryObjectModel extends SetQuery, Query { 61 }