SQL大查询优化

Question

我有以下查询：

SELECT `Product_has_ProductFeature`.`productId`, `Product_has_ProductFeature`.`productFeatureId`, `Product_has_ProductFeature`.`productFeatureValueId`
FROM `Product_has_ProductFeature`
WHERE `productId` IN (...'18815', '18816', '18817', '18818', '18819', '18820', '18821', '18822', '18823', '18824', '18825', '18826', '18827', '18828', '18829', '18830', '18831', '18832', '18833', '18834'..)

我有大约50000个productId。执行时间为20秒。我怎样才能让它更快？