Insert a distributor, or do nothing for rows proposed for insertion when an existing, excluded row (a row with a matching constrained column or columns after before row insert triggers fire) exists. Example assumes a unique index has been defined that constrains values appearing in the did column:
Suggesting this as replacement:
Insert a distributor, or do nothing if the proposed row conflicts with an existing row. Per-row triggers BEFORE INSERT are fired, and possible effects on the proposed applied, before checking for conflicts. Example assumes a unique index on the did column exists:
