How to convert this MYSQL SQL to HIVE SQL？ - sql

Question

The table ProductOrder columns include:
id shopid starttime endtime
1 123 2018-04-27 2018-04-28
2 234 2018-04-23 2018-04-30
3 189 2018-05-01 2018-05-30
4 321 2018-05-01 2018-05-29
I wan't to query for valid shop counts between two days and count by each day of latest month,the valid shop counts means the starttime<= $curDate <= endtime,and curDate is a variable of the each day of the leatest month.
Today is 2018-04-27，so the query result should be:
day count
2018-04-27 2
2018-04-26 1
2018-04-25 1
2018-04-24 1
2018-04-23 1
2018-04-22 0
2018-04-21 0
……………………………………
2018-03-26 0
I achieve this requirement in MYSQL.This SQL can work well in MYSQL.How can I convert to Hive Sql？
SELECT
DATE_SUB(DATE(NOW()), INTERVAL days_ago.days DAY) day,
COUNT(distinct(shopID)) count
FROM
(SELECT 0 days UNION SELECT 1 UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION
SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9 UNION
SELECT 10 UNION SELECT 11 UNION SELECT 12 UNION SELECT 13 UNION SELECT 14 UNION
SELECT 15 UNION SELECT 16 UNION SELECT 17 UNION SELECT 18 UNION SELECT 19 UNION
SELECT 20 UNION SELECT 21 UNION SELECT 22 UNION SELECT 23 UNION SELECT 24 UNION
SELECT 25 UNION SELECT 26 UNION SELECT 27 UNION SELECT 28 UNION SELECT 29)
AS days_ago
LEFT JOIN ProductOrder
ON DATE_SUB(DATE(NOW()), INTERVAL days_ago.days DAY) <= ProductOrder.endtime
AND DATE_SUB(DATE(NOW()), INTERVAL days_ago.days DAY) >= ProductOrder.starttime
AND status = 2
GROUP BY days_ago.days;

Answer 1

Hive does not support Non equi join conditions, they can be placed to the WHERE clause instead. Use STACK instead of many UNION subqueries.
select DATE_SUB(CURRENT_DATE, days_ago.days) day,
COUNT(DISTINCT(shopID)) count
from
(
select stack(30, --the number of elements
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
20, 21, 22, 23, 24, 25, 26, 27, 28, 29) as (days)
) days_ago
LEFT JOIN ProductOrder po ON status = 2
WHERE (DATE_SUB(CURRENT_DATE, days_ago.days) <= po.endtime
AND DATE_SUB(CURRENT_DATE, days_ago.days) >= po.starttime)
OR po.shopID is NULL --allow nulls
GROUP BY DATE_SUB(CURRENT_DATE, days_ago.days);

Answer 2

SELECT DATE_SUB(CURRENT_DATE, days_ago.days),
COUNT(DISTINCT(shopID)) count
FROM
(
SELECT explode(array(
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
20, 21, 22, 23, 24, 25, 26, 27, 28, 29)) as days
) days_ago
LEFT JOIN ProductOrder po ON
(
DATE_SUB(CURRENT_DATE, days_ago.days) <= po.endtime
AND DATE_SUB(CURRENT_DATE, days_ago.days) >= po.starttime
AND status = 2
)
GROUP BY days_ago.days;