使用表达式、别名和参数来代替硬编码
示例:
错误做法:
SELECT customer_id, 'China' AS country FROM orders WHERE ship_date > '2019-01-01';
正确做法:
SELECT customer_id, orders.country FROM orders WHERE ship_date > :date_parameter; -- 或者 SELECT customer_id, CASE country_code WHEN 'CN' THEN 'China' END AS country FROM orders WHERE ship_date > :date_parameter;
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