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When joining two tables in query, the system will create a join on similar keys. The EMPLID from one table will be joined to the EMPLID of another table; INSTITUTION will be joined with INSTITUTION, etc. Because INSTITUTION, BUSINESS_UNIT and SETID are defined differently, query will not create a join between them. The query writer must do it. So if the query needs to join two records, one of which has INSTITUTION as a key, another with BUSINESS_UNIT, the code first_table.INSTITUTION = second_table.BUSINESS_UNIT must be added manually. In CUNYfirst, the INSTITUTION always equals the BUSINESS_UNIT and SETID. The example has illustrated below:
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