SQL：Presto 中的交叉表等效项

Question

我有一个 table 看起来像这样：

shop    number  work    station accept  create  no.of entries
1   123 Maintain    Arrive  2019-10-11 0:00:00  2019-10-11 0:00:00  1
1   123 Maintain    WorkA   2019-10-11 0:00:00  2019-10-11 0:00:00  1
1   123 Maintain    WorkB   2019-10-11 0:00:00  2019-10-11 0:00:00  1
1   1234    Job Arrive  2019-10-11 0:00:00  2019-10-11 0:00:00  1
1   1234    Job WorkC   2019-10-11 0:00:00  2019-10-11 0:00:00  1
1   1234    Job WorkD   2019-10-11 0:00:00  2019-10-11 0:00:00  1

我想把它改成这样：

shop    number  work    arrival_accept  arrival_create  worka_accept    worka_create    workb_accept    workb_create    workc_accept    workc_create    workd_accept    workd_create    no.of entries
1   123 Maintain    2019-10-11 0:00:00  2019-10-11 0:00:00  2019-10-11 0:00:00  2019-10-11 0:00:00  2019-10-11 0:00:00  2019-10-11 0:00:00                  1
1   1234    Job 2019-10-11 0:00:00                      2019-10-11 0:00:00  2019-10-11 0:00:00  2019-10-11 0:00:00  2019-10-11 0:00:00  1

我知道在 postgres 中我们可以使用交叉表来实现这一点。但是，我无法用 Presto 做到这一点。我有办法做到这一点吗？

Answer 1

您可以使用条件聚合。如果你知道所有的电台，它看起来像：

select shop, number, work,
       max(case when station = 'Arrive' then accept end) as arrive_accept,
       max(case when station = 'Arrive' then create end) as arrive_create,
       max(case when station = 'WorkA' then accept end) as workA_accept,
       max(case when station = 'WorkA' then create end) as workA_create,
       . . .  -- and so on for the rest of the stations
from t
group by shop, number, work;

否则，您将需要动态构建查询以执行几乎相同的操作，但列数可变。

SQL：Presto 中的交叉表等效项

SQL: Crosstab equivalent in Presto

sql

pivot

crosstab

presto