678848=# select
678848-#        "wordFromId"( "word-id" ),
678848-#        "docnameFromId"( "doc-id" ),
678848-#        posns
678848-# from "word-doc"
678848-# where
678848-#        "word-id" in (
678848(#                "idFromWord"( 'aachen' ),
678848(#                "idFromWord"( 'zwitterions' )
678848(#        )
678848-# and
678848-#        "doc-id" in (
678848(#                select "docIdsContaining"( "idFromWord"( 'aachen' ) )
678848(#                intersect
678848(#                select "docIdsContaining"( "idFromWord"( 'zwitterions' ) )
678848(#        )
678848-# order by
678848-#        "word-id", "doc-id"
678848-# ;
 wordFromId  | docnameFromId | posns
-------------+---------------+-------
 aachen      | document_223  | 1723
 aachen      | document_940  | 1903
 aachen      | document_1778 | 273
 aachen      | document_1897 | 3163
 aachen      | document_3990 | 817
 aachen      | document_4407 | 4736
 zwitterions | document_223  | 3072
 zwitterions | document_940  | 3504
 zwitterions | document_1778 | 664
 zwitterions | document_1897 | 4186
 zwitterions | document_3990 | 355
 zwitterions | document_4407 | 1459
(12 rows)

678848=# select count( * ) from "word-doc";;
  count
---------
 2719282
(1 row)