noncanonical
noncanonical(T.a: text, T.b: text) 🡒 T.c : boolean, process
Returns true whenever a canonical representative for T.a cannot be computed. The pairs (T.a, T.b) are interpreted as graph edges with T.a as the source and T.b as the destination. The lack of representative happens when a circular path or a branching path gets detected.
Example:
table T = with
[| as OldCode, as Replacement |]
[| "x-00", "ax-00" |]
[| "x-01", "ax-01" |]
[| "x-02", "ax-02" |]
[| "ax-00", "x-00" |]
T.HasNoRepresentative = noncanonical(T.OldCode, T.Replacement)
show table "" a1c4 with
T.OldCode
T.Replacement
T.HasNoRepresentative
From a practical perspective, this process is intended to deal with code replacement (ex: SKU code replacement) as illustrated in the above example.