Запрос MySQL требует времени для запуска

Question

У меня есть запрос на MySQL, для выполнения которого требуется много времени.

Вот мой запрос:

SELECT DISTINCT *,ROUND((total_gross_profit- (payment_processor_holdout+payment_processor_fee)-(affiliate_commission_base+affiliate_commission_markup)),2) as net_profit FROM (SELECT O.id as oid 
,M.last_name 
,M.first_name 
,D.product_name 
,D.dosage_name 
,O.date 
,O.delivery 
,O.aff_id 
,IFNULL(O.product_total,0) as product_price 
,IFNULL(O.discount_amount,0) as purchase_discount 
,IFNULL((O.product_total - O.discount_amount),0) as net_sales 
,IFNULL(ROUND((O.total - O.product_total),2),0) as shipping_fee 
,IFNULL(ROUND(((O.product_total - O.discount_amount) - (O.total - O.product_total)),2),0) as gross_sales 
,IFNULL(P.unit_cost,0) as product_unit_cost 
,IFNULL((P.unit_cost * D.dosage_name),0) as costofgoods 
,aset.setting_value as shipping_cost 
,IFNULL(ROUND(((O.product_total - O.discount_amount) - (O.total - O.product_total) - (P.unit_cost * D.dosage_name)),2),0) as goods_gross_profit 
,IFNULL(ROUND(((O.total - O.product_total) - aset.setting_value),2),0) as shipping_gross_profit 
,(IFNULL(ROUND(((O.product_total - O.discount_amount) - (O.total - O.product_total) - (P.unit_cost * D.dosage_name)),2),0)+ IFNULL(ROUND(((O.total - O.product_total) - aset.setting_value),2),0)) as total_gross_profit 
,IFNULL(ROUND(IF(E.category_id IN (95,96,97,98,99),E.price*.25,E.price*.40),2),0) AS affiliate_commission_base 
,IFNULL(ROUND((F.price_markup*.50),2),0) AS affiliate_commission_markup 
,IFNULL((SELECT ppf.value FROM `aff_settings` ap 
LEFT JOIN `payment_processor_fee` ppf 
ON ap.setting_value=ppf.payment_processor_type 
WHERE ap.setting_name='payment_processor'),0) as payment_processor_fee 
,IFNULL(ROUND(((SELECT pph.value FROM `aff_settings` ap 
LEFT JOIN `payment_processor_holdout` pph 
ON ap.setting_value=pph.payment_processor_type 
WHERE ap.setting_name='payment_processor')* O.total),2),0) as payment_processor_holdout 
    FROM `order` as O 
    LEFT JOIN `order_detail` as D 
    ON O.id = D.order_id 
    LEFT JOIN `members` as M 
    ON M.id = O.buyer_id 
    LEFT JOIN `products` as P 
    ON P.generic_name = D.product_name 
    LEFT JOIN `aff_settings` as aset 
    ON aset.setting_name = O.delivery 
    LEFT JOIN `aff_order_details` as E 
    ON D.id = E.order_detail_ref_id 
    LEFT JOIN `aff_group_product_prices` as F 
    ON F.aff_id = O.aff_id 
    AND F.product_id =P.Id 
    AND F.dosage_id=D.dosage_name 
ORDER BY M.last_name) AS x 

У меня есть много соединяемых таблиц. Есть ли способ ускорить выполнение запроса? Если да, то как?

Благодарим за помощь.

Answer 1

Запустите EXPLAIN PLAN по этому запросу. Вероятно, вы увидите TABLE SCAN, что означает, что вам придется добавлять индексы и/или переписывать запрос.