Backward compatible change to add separation between the join conditions...

Backward compatible change to add separation between the join conditions returned by the RelatedBaseCategory method. Can be committed to trunk.

git-svn-id: https://svn.erp5.org/repos/public/erp5/sandbox/catalog_join@41962 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Catalog/CatalogTool.py

@@ -189,24 +189,47 @@ class RelatedBaseCategory(Method):
       self.strict_membership=strict_membership
       self.related = related
 
-    def __call__(self, instance, table_0, table_1, query_table='catalog', **kw):
-      """Create the sql code for this related key."""
+    def __call__(self, instance, table_0, table_1, query_table='catalog',
+                 RELATED_QUERY_SEPARATOR=' AND ',
+                 **kw):
+      """Create the sql code for this related key.
+
+      table_0 is the category table alias
+      table_1 is the catalog table alias for the related record
+      query_table is the catalog table (alias) for the main record.
+      """
       base_category_uid = instance.portal_categories._getOb(self._id).getUid()
       expression_list = []
       append = expression_list.append
+      # category selection and strict membership condition
+      append('%s.base_category_uid = %s' % (table_0,base_category_uid))
+      if self.strict_membership:
+        append('%s.category_strict_membership = 1' % table_0)
+      # join conditions:
       if self.related:
+        # query_table record is destination of relationship.
+        # 'on' condition for category join:
         append('%s.uid = %s.uid' % (table_1,table_0))
-        if self.strict_membership:
-          append('AND %s.category_strict_membership = 1' % table_0)
-        append('AND %s.base_category_uid = %s' % (table_0,base_category_uid))
-        append('AND %s.category_uid = %s.uid' % (table_0,query_table))
+        # 'on' condition for catalog join:
+        query_table_join = '%s.category_uid = %s.uid' % (table_0,query_table)
       else:
+        # query_table record is origin of relationship (i.e. the equivalent
+        # object contains the destination in its .category attribute)
+        # 'on' condition for category join:
         append('%s.uid = %s.category_uid' % (table_1,table_0))
-        if self.strict_membership:
-          append('AND %s.category_strict_membership = 1' % table_0)
-        append('AND %s.base_category_uid = %s' % (table_0,base_category_uid))
-        append('AND %s.uid = %s.uid' % (table_0,query_table))
-      return ' '.join(expression_list)
+        # 'on' condition for catalog join:
+        query_table_join = '%s.uid = %s.uid' % (table_0,query_table)
+      category_join = '\n AND \n'.join(expression_list)
+      # Since we relate two tables, we need to return two sets of
+      # conditions: one for the (inner) join between the two tables,
+      # and one for the join between the above and the main catalog
+      # table.
+      #
+      # These conditions are separated by RELATED_QUERY_SEPARATOR,
+      # which can be passed in by the caller if it wishes to separate
+      # the join condition on the catalog to generate an explicit inner join
+      expression = category_join + RELATED_QUERY_SEPARATOR + query_table_join
+      return expression
 
 class CatalogTool (UniqueObject, ZCatalog, CMFCoreCatalogTool, ActiveObject):
     """