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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?.
9 rows affected
ERROR: function last_day(date) does not exist
LINE 15: GROUP BY month_ld) f ON f.month_ld = LAST_DAY(s.sales_date...
^
HINT: No function matches the given name and argument types. You might need to add explicit type casts.