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SWDL3.1 A deal can be linked according to the following rules:
- SWDL3.1.1 A Source Deal can be part of only one Sales Deal link.
- SWDL3.1.2 A Source Deal, that is not linked to a Sales Deal, can be part of only one Liability Deal link.
- SWDL3.1.3 A Sales Deal can be part of only one Liability Deal link. And business users should be able to build ad-hoc queries in a query tool like MSQuery.
Requirement SWDL3.1.1 can be dealt with using a unique constraint.
Requirement SWDL3.1.3 can also be dealt with using a unique constraint.
Requirement SWDL3.1.2 is a bit more of a challenge. Because it requires knowledge of another table's relationships (whether there is a Sales Deal for a given Source Deal), it would need to be implemented as a trigger instead of a constraint.
I don't see any relationship between the requirements and the ability to use any particular query tool. Regardless of how these requirements are implemented, the user should be able to use any query tool that suits them (and is permitted/supported by corporate policy).
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This was first published in November 2002

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