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- G E O B A S E
- *************
-
- Geobase demonstrates a natural language interface to a database
- on U.S. geography. Geobase allows you to query its database in
- English rather than computerese. For a more complete discussion
- of Geobase and its features please refer to Appendix F in the
- Reference Guide.
-
- The database contains the following information:
-
- Information about states:
- Area of the state in square kilometers
- Population of the state in citizens
- Capital of the state
- Which states border a given state
- Rivers in the state
- Cities in the state
- Highest and lowest point in the state in meters
-
- Information about rivers:
- Length of river in kilometers
-
- Information about cities:
- Population of the city in citizens
-
-
- You can retrieve any or all of this information by asking questions
- in normal English. Some sample queries:
-
- - states
-
- - give me the cities in california.
-
- - what is the biggest city in california ?
-
- - what is the longest river in the usa?
-
- - which rivers are longer than 1 thousand kilometers?
-
- - what is the name of the state with the lowest point ?
-
- - which states border alabama ?
-
- - which rivers do not run through texas
-
- - which rivers run through states that border the state
- with the capital austin?
-
-
- You can modify Geobase as you work with it. If it doesn't
- understand a word in one of your questions, you can add the word
- to the language definition. The language is defined in a number
- of relations, the most important one being the schema. A schema
- is a description of the logical structure of a database. In
- Geobase, the schema is the "entity network" for the language. A
- schema entry follows the form: ENTITY ASSOCIATION ENTITY; this
- signifies that the two entities are bound together by the given
- association.
-
- To display the relations and their schema, select View Language
- from the Geobase main menu, then choose one of the items listed
- below.
-
-
- 1. Schema of relations
-
- The geographic data is stored in a number of relations. The
- schema for these relations is listed here.
-
- 2. Schema of questions
-
- The schema for all possible questions that can be asked is listed
- here. For example, one possibility is:
-
- > population of city <
-
- That is, what is the population of a given city?
-
- 3. Names of entities
-
- All known entities are listed here.
-
- 4. Synonyms for entities
-
- Synonyms for entities are allowed. The previously defined
- synonyms are listed here; you can also add synonyms to the
- database dynamically.
-
- 5. Synonyms for associations
-
- Synonyms for associations are allowed and can consist of
- more than one word.
-
- 6. Words that are ignored
-
- Some words are simply ignored by the system since they are not
- directly relevant to the meaning of questions. Ignored words are
- listed here.
-
- 7. Units for entities
-
- The units of measure for different entities are listed here. For
- instance, the unit for population is "number of citizens".
-
- 8. Synonyms for relational operators
-
- There are several ways to say that a city is "bigger than" 1 million
- citizens or that a river is "shorter than" 1 thousand miles. These
- synonyms are listed here.
-
- 9. Alternative ways to designate the minimum
-
- The different ways to designate adjectives for "minimum" are listed here.
-
- 10. Alternative ways to designate the maximum
-
- The different ways to designate adjectives for "maximum" are listed here.
-