优化 mysql 商品销售情况统计查询性能
问题描述：
针对如下 sql 查询：
select p.title,
count(o.id) as total,
coalesce(sum(o.amount), 0) as success_amount,
coalesce(sum(success.amount), 0) as failed_amount,
coalesce(sum(failed.amount), 0) as total_amount,
count(success.id) as success_total,
count(failed.id) as failed_total
from goods as g
left join orders as o on o.goods_id = g.id
left join orders as success on success.goods_id = g.id and success.status = 1
left join orders as failed on failed.goods_id = g.id and failed.status = 2
group by `p`.`id`
order by total desc
limit 10当查询时间范围较小时，查询速度较快，但当查询范围扩大时，查询速度极慢。
优化建议：
- 取消索引：删除 goods 表的 create_time 索引。
- 修改索引：将 orders 表的 goods_id 索引修改为 (create_time, goods_id, amount, status) 联合索引。
- 重写 sql：优化后的 sql 如下：
SELECT g.title,
COUNT(*) AS total,
COALESCE(SUM(o.amount), 0) AS total_amount,
COALESCE(SUM(IF(o.status = 1, o.amount, 0)), 0) AS success_amount,
COALESCE(SUM(IF(o.status = 2, o.amount, 0)), 0) AS failed_amount,
COALESCE(SUM(o.status = 1), 0) AS success_total,
COALESCE(SUM(o.status = 2), 0) AS failed_total
FROM orders AS o
JOIN goods AS g ON g.id = o.goods_id
WHERE o.create_time BETWEEN 'xxx' AND 'yyy'
GROUP BY o.id
ORDER BY total DESC
LIMIT 10注：
由于数据量较小（商品数量：8000，订单数量：100000），考虑使用 sqlite 代替 mysql 进行查询，可以获得较好的性能。
