如何在 SQL 中的同一个查询中创建多个视图，然后加入它们？

Question

这是我正在使用的查询。我需要加入三个视图来计算每月的总收入。我该如何进行？

With Txn as(
Select DATE_FORMAT(DATE_ADD(createdAt, interval 330 MINUTE), '%y-%m') as Month, Sum(netPrice/100) as TransactionRevenue from transactions 
group by Month)

With Leaves as(
Select DATE_FORMAT(DATE_ADD(createdAt, interval -1 MONTH), '%y-%m') as Month, sum(amount/100) as LeaveRevenue from driverPaymentTransactions
group by Month)

With Sxn as(
Select DATE_FORMAT(DATE_ADD(createdAt, interval 330 MINUTE ), '%y-%m') as Month, sum(amount/100) as SubscribedRevenue from subscribedDriversDailyRevenues
group by MONTH) 

Select * from Txn t
join Leaves l on t.Month = l.month
join Sxn s on t.month = s.month

Answer 1

With Txn as(
Select DATE_FORMAT(DATE_ADD(createdAt, interval 330 MINUTE), '%y-%m') as Month, Sum(netPrice/100) as TransactionRevenue from transactions 
group by Month),
Leaves as(
Select DATE_FORMAT(DATE_ADD(createdAt, interval -1 MONTH), '%y-%m') as Month, sum(amount/100) as LeaveRevenue from driverPaymentTransactions
group by Month),
Sxn as(
Select DATE_FORMAT(DATE_ADD(createdAt, interval 330 MINUTE ), '%y-%m') as Month, sum(amount/100) as SubscribedRevenue from subscribedDriversDailyRevenues
group by MONTH) 
Select * from Txn t
join Leaves l on t.Month = l.month
join Sxn s on t.month = s.month

Answer 2

您需要“加入”子查询

CREATE VIEw myview 
AS (With Txn as(
Select DATE_FORMAT(DATE_ADD(createdAt, interval 330 MINUTE), '%y-%m') as Month, Sum(netPrice/100) as TransactionRevenue from transactions 
group by Month)
, Leaves as(
Select DATE_FORMAT(DATE_ADD(createdAt, interval -1 MONTH), '%y-%m') as Month, sum(amount/100) as LeaveRevenue from driverPaymentTransactions
group by Month)
, Sxn as(
Select DATE_FORMAT(DATE_ADD(createdAt, interval 330 MINUTE ), '%y-%m') as Month, sum(amount/100) as SubscribedRevenue from subscribedDriversDailyRevenues
group by MONTH) 

Select * from Txn t
join Leaves l on t.Month = l.month
join Sxn s on t.month = s.month)

Answer 3

当您需要将一些不同的措施“拉”到公共属性时，请不要加入。使用union all，不需要关心组值最全来源：

create table t1 as
select 1 as id, 10 as val union all
select 1, 20 union all
select 2, 30 union all
select 3, 49

create table t2 as
select 1 as id, 10 as val union all
select 3, 20 union all
select 3, 30 union all
select 5, 49

create table t3 as
select 4 as id, 10 as val union all
select 6, 20 union all
select 2, 30 union all
select 3, 49

with u as (
  select
    id
    , val as t1_val
    , cast(null as decimal) as t2_val
    , cast(null as decimal) as t3_val
  from t1

  union all

  select
    id
    , null as t1_val
    , val as t2_val
    , null as t3_val
  from t2

  union all

  select
    id
    , null as t1_val
    , null as t2_val
    , val as t3_val
  from t3
)
select
  id
  , sum(t1_val) as t1_val
  , sum(t2_val) as t2_val
  , sum(t3_val) as t3_val
from u
group by id

id | t1_val | t2_val | t3_val
-: | -----: | -----: | -----:
 1 |     30 |     10 |   null
 2 |     30 |   null |     30
 3 |     49 |     50 |     49
 5 |   null |     49 |   null
 4 |   null |   null |     10
 6 |   null |   null |     20

db<>fiddle here

如何在 SQL 中的同一个查询中创建多个视图，然后加入它们？

How do I create multiple views in the same query in SQL and then join them?

mysql

sql

mariadb