根据您对我最初答案的评论,这里是另一个工作表。
表 DDL
create table tbl_order(
order_id integer,
account_number integer,
ordered_at date
);
您指出的其他线程中的数据
insert into tbl_order values (1, 1001, to_date('10-Sep-2019 00:00:00', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (2, 2001, to_date('01-Sep-2019 00:00:00', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (3, 2001, to_date('03-Sep-2019 00:00:00', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (4, 1001, to_date('12-Sep-2019 00:00:00', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (5, 3001, to_date('18-Sep-2019 00:00:00', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (6, 1001, to_date('20-Sep-2019 00:00:00', 'DD-MON-YYYY HH24:MI:SS'));
查询
WITH VW AS (
SELECT ACCOUNT_NUMBER,
MIN(ORDERED_AT) EARLIEST_ORDER_AT,
MAX(ORDERED_AT) LATEST_ORDER_AT,
ROUND(MAX(ORDERED_AT) - MIN(ORDERED_AT), 5) DIFF_IN_DAYS,
COUNT(*) TOTAL_ORDER_COUNT
FROM TBL_ORDER
GROUP BY ACCOUNT_NUMBER
)
SELECT ACCOUNT_NUMBER, EARLIEST_ORDER_AT, LATEST_ORDER_AT,
DIFF_IN_DAYS, ROUND( DIFF_IN_DAYS/TOTAL_ORDER_COUNT, 4) AVERAGE
FROM VW;
结果
===========以后的初步回答===========
例如你的问题并不完全清楚
- 您希望每天的日期不同(用户每天可以下多份订单)还是仅在他们最早和最新的订单之间存在差异
- 平均是什么意思,它只是(最晚订单日期 - 最早订单日期)/总购买量?这将是小时/购买。有用吗?
无论如何,这是一个工作表,它足以让你朝着正确的方向前进(希望如此)。这适用于 Oracle 数据库,除了这里使用的时间转换功能外,主要适用于其他数据库。如果不是 Oracle,您将不得不为您选择的数据库搜索和使用等效功能。
创建表
create table tbl_order(
order_id integer,
user_id integer,
item varchar2(100),
ordered_at date
);
插入一些数据
insert into tbl_order values (8, 1, 'A2Z', to_date('21-Mar-2019 16:30:20', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (1, 1, 'ABC', to_date('22-Mar-2019 07:30:20', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (2, 1, 'ABC', to_date('22-Mar-2019 07:30:20', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (3, 1, 'EFGT', to_date('22-Mar-2019 09:30:30', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (4, 1, 'XYZ', to_date('22-Mar-2019 12:38:50', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (5, 1, 'ABC', to_date('22-Mar-2019 16:30:20', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (6, 2, 'ABC', to_date('22-Mar-2019 14:20:20', 'DD-MON-YYYY HH24:MI:SS'));
insert into tbl_order values (7, 2, 'A2C', to_date('22-Mar-2019 14:20:50', 'DD-MON-YYYY HH24:MI:SS'));
获取每个用户的最新、最早和总购买量以及平均值
WITH VW AS (
SELECT USER_ID,
TO_CHAR(MIN(ORDERED_AT), 'DD-MON-YYYY HH24:MI:SS') EARLIEST_ORDER_AT,
TO_CHAR(MAX(ORDERED_AT), 'DD-MON-YYYY HH24:MI:SS')LATEST_ORDER_AT,
ROUND(MAX(ORDERED_AT) - MIN(ORDERED_AT), 5) * 24 DIFF_IN_HOURS,
COUNT(*) TOTAL_ORDER_COUNT
FROM TBL_ORDER
GROUP BY USER_ID
)
SELECT USER_ID, EARLIEST_ORDER_AT, LATEST_ORDER_AT,
DIFF_IN_HOURS, DIFF_IN_HOURS/TOTAL_ORDER_COUNT AVERAGE
FROM VW;
获取每位用户每天的最新、最早和总购买量以及平均值
WITH VW AS (
SELECT USER_ID, TO_CHAR(ORDERED_AT, 'DD-MON-YYYY') ORDER_DATE_PART,
TO_CHAR(MIN(ORDERED_AT), 'DD-MON-YYYY HH24:MI:SS') EARLIEST_ORDER_AT,
TO_CHAR(MAX(ORDERED_AT), 'DD-MON-YYYY HH24:MI:SS')LATEST_ORDER_AT,
ROUND(MAX(ORDERED_AT) - MIN(ORDERED_AT), 5) * 24 DIFF_IN_HOURS,
COUNT(*) TOTAL_ORDER_COUNT
FROM TBL_ORDER
GROUP BY USER_ID, TO_CHAR(ORDERED_AT, 'DD-MON-YYYY')
)
SELECT USER_ID, ORDER_DATE_PART, EARLIEST_ORDER_AT, LATEST_ORDER_AT,
DIFF_IN_HOURS, DIFF_IN_HOURS/TOTAL_ORDER_COUNT AVERAGE
FROM VW;