如果另一个字段等于5或10，则不要乘以字段

Question

我正在运行这个查询，它正在填充我的临时表，然后我从中导出。 priceSingle是通过简单地加倍票价来计算的。但是，对于某些行，该类别无论如何都是单一票价，所以我不想加倍。该查询实际上嵌入在PHP中的字符串中，但SQL看起来像：

INSERT INTO temp
    SELECT cruises.code AS sailingId, live, 'USD', 'optioncode', 'rateOptionName', '2',
           category AS cabinCategory, fare*2 AS priceSingle, fare AS priceDouble,
           supplements_usa.adult AS priceAdditional
      FROM fares_usa, supplements_usa, cruises
     WHERE fares_usa.cruise_id = supplements_usa.cruise_id
       AND cruises.id = fares_usa.cruise_id AND cruises.live = 'Y'

当fare*2等于5或10时，如何避免category？

Answer 1

CASE WHEN category = 5 OR category = 10 THEN fare ELSE fare * 2 END