There are a number of BUGS related to the issue of
uniqueness in data models.
When a Foreign Key Constraint is defined on a uniquely constrained columnSet in the origin (source) table, the source multiplicity MUST be set to 1. Similarly, if a FK columnSet is subsequently marked as unique, then the source multiplicity MUST be updated to 1 also.
Removal of the uniqueness constraint MUST reset the source multiplicity to 0..* (NOT generate an error message such as at present (EA 6.5(805)))
Marking a column as unique subsequent to its creation MUST regenerate a uniqueness constraint. Taking off the constraint will remove the constraint, but putting it back on doesn't regenerate it. A subtle consequence of this bug is that indexes that may not be marked as unique MUST be marked as unique if any column in them is unique. My testing reveals that EA does not currently do this.
After adding a column to an operation as a parameter, it should no longer be available in the dropdown list for that operation. (Unlike ordinary operations, TABLE operations can/should
1 only use the column once.)
Thoughts? (Votes aren't required - these are DEFECTS)
Paolo
[size=0]©2007 Paolo Cantoni, -Semantica-[/size]
1It is theoretically possible for some operations to redundantly use the same column - for example an index with the same column specified more than once - but this is
reductio ad absurdam.
