Rails 3.2、Ruby 1.9、ジオコーダー gem を使用。コントローラーに次のクエリがあります。
# 1500+ms to load
nearby_shops = (current_shop.nearbys(10, :order => 'overall_rating DESC')
.where(:shop_type => shop_type).includes(:photos, :active_property_list =>
:hotel_image_lists).limit(5))
# SQL
Shop Load (4045.6ms) SELECT shops.*, 3958.755864232 * 2 * ASIN(SQRT(POWER(
SIN((36.111927 - shops.lat) * PI() / 180 / 2), 2) + COS(36.111927 * PI()
/ 180) * COS(shops.lat * PI() / 180) * POWER(SIN((-115.171229 - shops.lng)
* PI() / 180 / 2), 2))) AS distance, CAST(DEGREES(ATAN2( RADIANS(shops.lng
- -115.171229), RADIANS(shops.lat - 36.111927))) + 360 AS decimal) % 360 AS
bearing FROM `shops` WHERE `shops`.`shop_type` = 'food' AND (shops.lat BETWEEN
35.96719521688915 AND 36.25665878311085 AND shops.lng BETWEEN
-115.3503819353204 AND -114.9920760646796 AND 3958.755864232 * 2 *
ASIN(SQRT(POWER(SIN((36.111927 - shops.lat) * PI() / 180 / 2), 2) +
COS(36.111927 * PI() / 180) * COS(shops.lat * PI() / 180) * POWER(SIN((
-115.171229 - shops.lng) * PI() / 180 / 2), 2))) <= 10 AND shops.id != 85155)
ORDER BY overall_rating DESC LIMIT 5
- shops.lat) * PI() / 180 / 2), 2) + COS(48.8582411618 * PI() / 180) *
COS(shops.lat * PI() / 180) * POWER(SIN((2.2945044899 - shops.lng) * PI() /
180 / 2), 2))) <= 100 AND shops.id != 517) ORDER BY distance ASC LIMIT 25
OFFSET 0
問題は、nearbysと で計算を行う にlongitudeありlatitudeます。longitudeおよび列にインデックスを既に追加しましたlatitudeが、何も改善されません。
どうすればこれを改善できますか?
P/S: クエリの速度に寄与しない無関係な条件を削除しました。