MariaDB 10.5

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create table ReceiptItem (retailprice int, vat int)
create or replace view v_ReceiptSumByVAT
as
select VAT, SUM(RetailPrice) / (1 + VAT) as Sum from ReceiptItem
  group by VAT
select view_definition
from information_schema.views


view_definition


select `db_717038699`.`ReceiptItem`.`vat` AS `VAT`,sum(`db_717038699`.`ReceiptItem`.`retailprice`) / 1 + `db_717038699`.`ReceiptItem`.`vat` AS `Sum` from `db_717038699`.`ReceiptItem` group by `db_717038699`.`ReceiptItem`.`vat`