org.nuxeo.ecm.core.storage.sql.jdbc
Class NXQLQueryMaker

java.lang.Object
  org.nuxeo.ecm.core.storage.sql.jdbc.NXQLQueryMaker

All Implemented Interfaces:

QueryMaker

Direct Known Subclasses:

TagQueryMaker

public class NXQLQueryMaker
extends java.lang.Object
implements QueryMaker

Transformer of NXQL queries into underlying SQL queries to the actual database.

The examples below are based on the NXQL statement:

 SELECT * FROM File
 WHERE
   dc:title = 'abc'
   AND uid:uid = '123'
   AND dc:contributors = 'bob'    -- multi-valued
 

If there are no proxies (ecm:isProxy = 0) we get:

 SELECT hierarchy.id
   FROM hierarchy
   LEFT JOIN dublincore ON hierarchy.id = dublincore.id
   LEFT JOIN uid ON hierarchy.id = uid.id
 WHERE
   hierarchy.primarytype IN ('File', 'SubFile')
   AND dublincore.title = 'abc'
   AND uid.uid = '123'
   AND EXISTS (SELECT 1 FROM dc_contributors WHERE hierarchy.id = dc_contributors.id
               AND dc_contributors.item = 'bob')
   AND NX_ACCESS_ALLOWED(hierarchy.id, 'user1|user2', 'perm1|perm2')
 

The data tables (dublincore, uid) are joined using a LEFT JOIN, as the schema may not be present on all documents but this shouldn't prevent the WHERE clause from being evaluated. Complex properties are matched using an EXISTS and a subselect. When proxies are matched (ecm:isProxy = 1) there are two additional FULL JOINs. Security checks, id, name, parents and path use the base hierarchy (_H), but all other data use the joined hierarchy.

 SELECT _H.id
   FROM hierarchy _H
   JOIN proxies ON _H.id = proxies.id                     -- proxy full join
   JOIN hierarchy ON hierarchy.id = proxies.targetid      -- proxy full join
   LEFT JOIN dublincore ON hierarchy.id = dublincore.id
   LEFT JOIN uid ON hierarchy.id = uid.id
 WHERE
   hierarchy.primarytype IN ('File', 'SubFile')
   AND dublincore.title = 'abc'
   AND uid.uid = '123'
   AND EXISTS (SELECT 1 FROM dc_contributors WHERE hierarchy.id = dc_contributors.id
               AND dc_contributors.item = 'bob')
   AND NX_ACCESS_ALLOWED(_H.id, 'user1|user2', 'perm1|perm2') -- uses _H
 

When both normal documents and proxies are matched, we UNION ALL the two queries. If an ORDER BY is requested, then columns from the inner SELECTs have to be aliased so that an outer ORDER BY can user their names.

Author:

Florent Guillaume

Nested Class Summary

class	NXQLQueryMaker.QueryAnalyzer Collects various info about the query AST, and rewrites the toplevel AND Predicates of the WHERE clause into a single MultiExpression for easier analysis.
static class	NXQLQueryMaker.WhereBuilder Builds the database-level WHERE query from the AST.

Nested classes/interfaces inherited from interface org.nuxeo.ecm.core.storage.sql.jdbc.QueryMaker

QueryMaker.Query, QueryMaker.QueryCannotMatchException, QueryMaker.QueryMakerException

Field Summary

static java.lang.String	TYPE_DOCUMENT
static java.lang.String	TYPE_RELATION

Constructor Summary

NXQLQueryMaker()

Method Summary

boolean	accepts(java.lang.String queryString) Checks if this query maker accepts a given query.
QueryMaker.Query	buildQuery(SQLInfo sqlInfo, Model model, Session.PathResolver pathResolver, java.lang.String query, QueryFilter queryFilter, java.lang.Object... params) Builds the query.
java.lang.String	getName() Gets the name for this query maker.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

TYPE_DOCUMENT

public static final java.lang.String TYPE_DOCUMENT

See Also:

Constant Field Values

TYPE_RELATION

public static final java.lang.String TYPE_RELATION

See Also:

Constant Field Values

Constructor Detail

NXQLQueryMaker

public NXQLQueryMaker()

Method Detail

getName

public java.lang.String getName()

Description copied from interface: QueryMaker

Gets the name for this query maker.

Specified by:

getName in interface QueryMaker

accepts

public boolean accepts(java.lang.String queryString)

Description copied from interface: QueryMaker

Checks if this query maker accepts a given query.

Called first.

Specified by:

accepts in interface QueryMaker

Parameters:

queryString - the query

Returns:

true if the query is accepted

buildQuery

public QueryMaker.Query buildQuery(SQLInfo sqlInfo,
                                   Model model,
                                   Session.PathResolver pathResolver,
                                   java.lang.String query,
                                   QueryFilter queryFilter,
                                   java.lang.Object... params)
                            throws StorageException

Description copied from interface: QueryMaker

Builds the query.

Specified by:

buildQuery in interface QueryMaker

Parameters:

sqlInfo - the sql info

model - the model

pathResolver - the path resolver

query - the query

queryFilter - the query filter

params - additional parameters, maker-specific

Throws:

StorageException