Though it should never be the case, a scryfall data dump included a card
wherein the oracle text differed between variants having the same oracle
id. Using DISTINCT ON with an ORDER BY clause will select just one
distinct version of these fields to be inserted into the database.
The dump from 20230617212037 included a single oracle entry breaking
this assumed guarantee with versions containing differing oracle text:
\x on
SELECT DISTINCT "oracle_id"
, "name"
, "color_identity"
, "cmc"
, "mana_cost"
, "type_line"
, "edhrec_rank"
, "oracle_text"
FROM "tmp_cards"
WHERE "tmp_cards"."oracle_id" = '5feedfb0-30e6-400d-9e28-d541ea1aa14e';
oracle_id 5feedfb0-30e6-400d-9e28-d541ea1aa14e
name Plague Spitter
color_identity B
cmc 3.00
mana_cost {2}{B}
type_line Creature — Phyrexian Horror
edhrec_rank 7226
oracle_text At the beginning of your upkeep, Plague Spitter deals 1 damage to each creature and each player.
When Plague Spitter dies, Plague Spitter deals 1 damage to each creature and each player.
oracle_id 5feedfb0-30e6-400d-9e28-d541ea1aa14e
name Plague Spitter
color_identity B
cmc 3.00
mana_cost {2}{B}
type_line Creature — Phyrexian Horror
edhrec_rank 7226
oracle_text At the beginning of your upkeep, Plague Spitter deals 1 damage to each creature and each player.
When Plague Spitter dies, it deals 1 damage to each creature and each player.