如何优化此SQL查询

如何解决如何优化此SQL查询

我想计算完成一项特定任务的不同用户的数量，并将其分类。

SELECT 
    u.`source_of_registration`,COUNT(disTINCT u.users_id),SUM(CASE WHEN o.onboarding_statuses_id=4  THEN 1 ELSE 0 END) AS "KYC completed",SUM(CASE WHEN datediff(o.`created_at`,u.`created_at`)<=3 AND o.`onboarding_statuses_id`=4 THEN 1 ELSE 0 END)AS "KYC completion TAT <3 days",u.`created_at`)>3  AND o.`onboarding_statuses_id`=4 THEN 1 ELSE 0 END)AS "KYC complation TAT >3 days",SUM(CASE WHEN o.onboarding_statuses_id=7  THEN 1 ELSE 0 END) AS "KYC verified",u.`created_at`)<=3  AND o.`onboarding_statuses_id`=7 THEN 1 ELSE 0 END)AS "KYC verification TAT <3 days",u.`created_at`)>3  AND o.`onboarding_statuses_id`=7 THEN 1 ELSE 0 END)AS "KYC verification TAT >3 days",COUNT(disTINCT CASE WHEN i.`bank_connection_statuses_id`=1 THEN u.users_id ELSE NULL END) AS "BankConnected",COUNT(disTINCT CASE WHEN  ex.users_id IN (SELECT u.users_id FROM users u WHERE u.created_at > "2020-07-31 00:00:00") OR l.users_id IN (SELECT u.users_id FROM users u WHERE u.created_at > "2020-07-31 00:00:00") THEN u.users_id ELSE NULL END )AS "F",COUNT(disTINCT CASE WHEN datediff(ex.`created_at`,u.`created_at`)<=3 OR datediff(l.created_at,u.created_at)<=3 THEN u.users_id ELSE NULL END )AS "First trxn TAT < 3",u.`created_at`)>3 AND datediff(l.created_at,u.created_at)>3 THEN u.users_id ELSE NULL END )AS "First trxn TAT > 3"
FROM 
    users u USE INDEX(users_id) 
LEFT JOIN 
    `onboarding_status_histories` o ON u.users_id = o.users_id 
LEFT JOIN 
    companies c ON c.users_id = u.users_id 
LEFT JOIN   
    `external_fund_transfers` ex ON u.users_id = ex.users_id 
LEFT JOIN 
    `icici_connected_accounts` i ON i.users_id = u.users_id 
LEFT JOIN 
    `live_account_balance_histories` l ON l.users_id = u.users_id  
WHERE 
    u.created_at BETWEEN "2020-08-01 00:00:00" AND "2020-08-01 23:59:59" 
    AND u.`source_of_registration` IN ("m.bankonnect.co","app.bankonnect.co") GROUP BY 
    `source_of_registration`