- All Superinterfaces:
- Query, QueryCommand, SetQuery
- All Known Implementing Classes:
public interface SetQueryObjectModel
- extends SetQuery, Query
A set query extension to the JCR query object model.
The JCR query object model describes the queries that can be evaluated by a JCR repository independent of any particular query
language, such as SQL. JCR defines the
QueryObjectModel interface as the primary representatino of this query object
model, but this interface is not sufficient for certain queries, such as unions or intersections of other queries. This
interface is an extension to the JCR API that mirrors the QueryObjectModel interface for set queries.
A query consists of:
- a source. When the query is evaluated, the source evaluates its selectors and the joins between them to produce a (possibly
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
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
- an optional constraint. When the query is evaluated, the constraint filters the set of node-tuples.
- a list of zero or more orderings. The orderings specify the order in which the node-tuples appear in the query results. The
relative order of two node-tuples is determined by evaluating the specified orderings, in list order, until encountering an
ordering for which one node-tuple precedes the other. If no orderings are specified, or if for none of the specified orderings
does one node-tuple precede the other, then the relative order of the node-tuples is implementation determined (and may be
- a list of zero or more columns to include in the tabular view of the query results. If no columns are specified, the
columns available in the tabular view are implementation determined, but minimally include, for each selector, a column for
each single-valued non-residual property of the selector's node type.
The query object model representation of a query is created by factory methods in the
- See Also:
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