Canadian Maple Trees, Inc. has a distributed relational database with tables in computers in Halifax, Montreal, Ottawa, Toronto, and Vancouver.
The database consists of twelve tables, some of which are replicated in multiple cities. Among them are tables A, B, and C, with the following characteristics.
Table A consists of 800,000 records and is located in Halifax, Montreal, and Vancouver.
Table B consists of 100,000 records and is located in Halifax and Toronto.
Table C consists of 20,000 records and is located in Ottawa and Vancouver.
Telecommunications costs among Montreal, Ottawa, and Toronto are relatively low, while telecommunications costs between those three cities and Halifax and Vancouver are relatively high.
A query is issued from Montreal that requires a join of tables A, B, and C. The query involves a single record from table A, 20 records from table B, and an undetermined number of records from table C. Develop and justify a plan for solving this query.