我们可以直接使用指令,从URL指向的文件中获取内容并导入表。但是担心网络不稳定,我们先将文件下载下来。...查询
SELECT toYear(date), district, town, avg(price), sum(price), count() FROM uk_price_paid GROUP BY...新增PROJECTION
使用下面指令给toYear(date), district, town创建一个PROJECTION ,这样之后插入的数据就会被自动优化。...projection_by_year_district_town(SELECT toYear(date), district, town, avg(price), sum(price), count() GROUP...优化后查询
80441 rows in set. Elapsed: 0.170 sec.