0205 — Reads name their columns explicitly; SELECT * is out
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Context. readMessages used SELECT * against message_log. When the
table grew a routing_key column that MessageRow had no field for,
pgx.RowToStructByName errored on the unmapped column — it does not silently
ignore extras — so the CURSOR read path was silently broken from the moment
the column landed until this phase’s own live verification caught it.
Decision. readMessages selects explicit columns; SELECT * is
abandoned as a pattern.
Consequences. Additive schema changes stop being breaking for existing
readers: a new column is invisible to a query that never names it. This
incident settled the codebase-wide rule that every query names its columns.
Rejected: SELECT * — couples every reader’s scan destination to the
table’s full width, turning a column ADD into a runtime error.