Cross-product ( the "X" operator) question

[xochi]

The cross-product operator (choosing the "X" instead of "=" or less than , greater than, etc.) maps all records of one table to all records of another, right?

If so, why do we need to pick a field on each side of the relationship? Shouldn't this cross-product relation be from table-to-table?

For clarity, I tend to just choose a serial number or primary key field, but wouldn't it be cleaner and clearer if the cross-product relationship didn't require you to specify key fields?

[xochi]

The cross-product operator (choosing the "X" instead of "=" or less than , greater than, etc.) maps all records of one table to all records of another, right?

If so, why do we need to pick a field on each side of the relationship? Shouldn't this cross-product relation be from table-to-table?

For clarity, I tend to just choose a serial number or primary key field, but wouldn't it be cleaner and clearer if the cross-product relationship didn't require you to specify key fields?

[xochi]

The cross-product operator (choosing the "X" instead of "=" or less than , greater than, etc.) maps all records of one table to all records of another, right?

If so, why do we need to pick a field on each side of the relationship? Shouldn't this cross-product relation be from table-to-table?

For clarity, I tend to just choose a serial number or primary key field, but wouldn't it be cleaner and clearer if the cross-product relationship didn't require you to specify key fields?

[Martin Brändle]

In principle yes. But: The user interface for "define database" and "edit relationship" would not be as consistent as it is now; one would need to have an additional dialog box (e.g. for "delete related records in this table when a record is deleted in the other table" (did you try out with the cross operator? All records are deleted)). Now you can combine several relation operators within one dialog box only.

Martin

[Martin Brändle]

In principle yes. But: The user interface for "define database" and "edit relationship" would not be as consistent as it is now; one would need to have an additional dialog box (e.g. for "delete related records in this table when a record is deleted in the other table" (did you try out with the cross operator? All records are deleted)). Now you can combine several relation operators within one dialog box only.

Martin

[Martin Brändle]

In principle yes. But: The user interface for "define database" and "edit relationship" would not be as consistent as it is now; one would need to have an additional dialog box (e.g. for "delete related records in this table when a record is deleted in the other table" (did you try out with the cross operator? All records are deleted)). Now you can combine several relation operators within one dialog box only.

Martin