[Patents] EPO prohibits natlang based database queries

[PILCH Hartmut phm@a2e.de]

EP0522591 
Database retrieval system for responding to natural language queries with 
corresponding tables
MITSUBISHI ELECTRIC CORP (JP)

The following claims seem to cover anything that is done when translating
natural language questions into database queries.  The real difficulty
lies in writing the parsers and "virtual tables" that Mitsubishi tells the
ordinary man skilled in the art to use, but about those nothing is
disclosed.  

   Claims
   
   1. An information retrieval system for retrieving information from a
   database, comprising:
   a parser for parsing a natural language query into its constituent
   phrases to produce a syntax analysis result;
   virtual table for converting phrases of the natural language query to
   retrieval keys possessed by the database, said virtual table
   accounting for particles that modify the phrases;
   a collating unit for preparing a database retrieval formula from the
   syntax analysis result by selecting a virtual table that is used to
   convert the phrases of the natural language query to keys possessed by
   the database; and
   a retrieval execution unit for retrieving data from the database on
   the basis of said database retrieval formula.
   2. An information retrieval system as recited in Claim 1 further
   comprising;
   an additional table for converting an undetermined value phrase in the
   natural language query into a determined value phrase in the database
   based on the syntax analysis result.
   3. An information retrieval system as recited in Claim 1 further
   comprising;
   a terminology dictionary for identifying entries in the virtual table
   to be used in converting the phrases of natural language query, said
   dictionary including words representing time, and said terminology
   dictionary being used by the parser in obtaining the syntax analysis
   result; and
   a time interval definition table in the virtual table for defining
   dates corresponding to said words representing time.
   4. An information retrieval system as recited in Claim 1 further
   comprising;
   a database retrieval formula conversion unit for generating a formula
   in a database retrieval language from the database retrieval formula.
   5. An information retrieval system for retrieving information from a
   database, comprising: :
   a parser for parsing a natural language query into its constituent
   phrases to produce a syntax analysis result;
   virtual table for converting phrases of the natural language query to
   retrieval keys possessed by the database, said virtual table
   accounting for particles that modify the phrases;
   a collating unit for preparing a database retrieval formula from the
   syntax analysis result by selecting a virtual table that is used to
   convert the phrases of the natural language query to keys possessed by
   the database;
   a retrieval execution unit for retrieving data from the database on
   the basis of said database retrieval formula;
   an additional table for converting an undetermined value phrase in the
   natural language query into a determined value phrase in the database
   based on the syntax analysis result; ;
   a terminology dictionary for identifying entries in the virtual table
   to be used in converting the phrases of natural language query, said
   dictionary including words representing time, and said terminology
   dictionary being used by the parser in obtaining the syntax analysis
   result;
   a time interval definition table in the virtual table for defining
   dates corresponding to said words representing time; and
   a database retrieval formula conversion unit for generating a formula
   in a database retrieval language from the database retrieval formula.
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   Data supplied from the esp@cenet database - l2