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Help with an interesting Postgres question: Why isn't an Index Only Scan used on a partition accessed via the parent table?.
WITH t(js) AS
(
SELECT '[ { "state" : "CA", "tax_amount" : 3},
{ "state" : "AZ", "tax_amount" : 4}]'::JSONB
)
SELECT SUM(tax_amount) AS total_tax_amount
FROM t
CROSS JOIN JSONB_POPULATE_RECORDSET(NULL::record,js )
AS tab(state VARCHAR(10), tax_amount INT)
| total_tax_amount |
|---|
| 7 |