我有3个表(provider、provider_has_product、product):
(原文:)SELECT DISTINCT `provider_has_product2行的Error Code: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQLsyntax to use near 'SELECT * FROMproductWHERE NOT EXIST
select ((x.am1998-x.am1999)/ ((x.am1998+x.am1999)/2)) as answer from(sum(amount) FILTER(where EXTRACT(YEAR FROM order_date)=1999)) as am1999 from orders) x;
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