简单查询但速度慢

Question

我在Mysql中有以下查询速度很慢。我在表price_all中有date,close,sec的索引。 price_all表中有超过100,000,000行。

SELECT date, close FROM `price_all` where sec=? AND date>? order by date

EXPLAIN输出

Answer 1

日期排序很慢。试试

SELECT UNIX_TIMESTAMP(date), date, close FROM `price_all` where sec=? AND date>? order by 1