doUpdate
Updates the existing row.
The assignment is SQL, so the values on the right come from excluded - PostgreSQL's name for the row that could not be inserted - or from the target table, or from anywhere else an expression may look: doUpdate("cognomen = excluded.cognomen, updated_at = now()").
Parameters
setExpression
The SET body, written out.
whereCondition
An optional condition on the update, which is how a conflict resolves to "update only where it is worth updating".
As doUpdate, with the assignments given as column-to-expression pairs.
As doUpdate, with the assignments given as a column-to-expression map.