Maintaining cardinality of rows while joining worksheets from a database

An apparatus for maintaining cardinality of rows while joining worksheets from a database, the apparatus comprising a computer processor, a computer memory operatively coupled to the computer processor, the computer memory having disposed within it computer program instructions that, when executed by the computer processor, cause the apparatus to carry out the steps of:

• receiving a request to join, to a first worksheet, a second worksheet from the database;
• for each row in the first worksheet:
• generating a join row for data from the second worksheet on the database;
• in response to determining that there is at least one matching row in the second worksheet on the database:
• compare a maximum value and a minimum value for each column in each row of the at least one matching row;
• if the maximum value and the minimum value match, store a matching value in a corresponding column of the join row;
• and
• if the maximum value and the minimum value do not match, store a multiple value indication in the corresponding column of the join row;
• and
• presenting the join row adjacent to a corresponding row in the first worksheet.

A computer program product for maintaining cardinality of rows while joining worksheets from a database, the computer program product disposed upon a computer readable medium, the computer program product comprising computer program instructions that, when executed, cause a computer to carry out the steps of:

• receiving a request to join, to a first worksheet, a second worksheet from the database;
• for each row in the first worksheet:
• generating a join row for data from the second worksheet on the database;
• in response to determining that there is at least one matching row in the second worksheet on the database:
• compare a maximum value and a minimum value for each column in each row of the at least one matching row;
• if the maximum value and the minimum value match, store a matching value in a corresponding column of the join row;
• and
• if the maximum value and the minimum value do not match, store a multiple value indication in the corresponding column of the join row;
• and
• presenting the join row adjacent to a corresponding row in the first worksheet.