update of a column based on max date and group by - sql

Question

i have three tables orders, orders_delivered, orders_delivered_sta
and the data in the three tables look like
table orders
orders_id
10
11
12
13
table orders_delivered
orders_delivered_id orders_id
10 1000
10 1001
11 1002
12 1003
12 1004
13 1005
13 1006
13 1007
table orders_delivered_sta
orders_delivered_sta_id orders_delivered_id date now_ind
1 1000 02/11/2011 0
2 1000 01/10/2006 0
3 1000 09/13/2011 0
4 1001 01/19/2010 0
5 1001 02/21/2011 0
6 1002 02/11/2009 0
7 1002 08/27/2010 0
8 1003 07/15/2012 0
9 1004 03/09/2007 0
10 1010 10/01/2010 0
11 1011 03/27/2011 0
12 1012 07/25/2010 0
13 1013 09/18/2004 0
so i need to update orders_delivered_sta table such that now_ind should be 1 for the max date of one orders_delivered_id
like for one orders_delivered_id 1000 the max date is 09/13/2011 for this set of orders_delivered_id and date (1000,09/13/2011) the now_ind should be 1 and if the column orders_delivered_id has one and only one id then that should be changed to 1
there is some data in orders_delivered_sta table which are not in orders and orders_delivered tables those need not to be changed. the orders_delivered_id which are in oreders_delivered table only needs to change
so the desired output should look like
table orders_delivered_sta
orders_delivered_sta_id orders_delivered_id date now_ind
1 1000 02/11/2011 0
2 1000 01/10/2006 0
3 1000 09/13/2011 1
4 1001 01/19/2010 0
5 1001 02/21/2011 1
6 1002 02/11/2009 0
7 1002 08/27/2010 1
8 1003 07/15/2012 1
9 1004 03/09/2007 1
10 1010 10/01/2010 0
11 1011 03/27/2011 0
12 1012 07/25/2010 0
13 1013 09/18/2004 0
table structure:
create table orders
(
order_id int primary key
)
insert into orders select 10
insert into orders select 11
insert into orders select 12
insert into orders select 13
create table orders_delivered
(
orders_delivered_id int primary key,
orders_id int FOREIGN KEY(orders_id)REFERENCES orders (orders_id)
)
insert into orders_delivered select 1000,10
insert into orders_delivered select 1001,10
insert into orders_delivered select 1002,11
insert into orders_delivered select 1003,12
insert into orders_delivered select 1004,12
insert into orders_delivered select 1005,13
insert into orders_delivered select 1006,13
insert into orders_delivered select 1007,13
create table orders_delivered_sta
(
orders_delivered_sta_id int primary key,
orders_delivered_id int FOREIGN KEY(orders_delivered_id)REFERENCES orders_delivered (orders_delivered_id),
date char(10),
now_ind int
)
insert into orders_delivered_sta select 1,1000,'02/11/2011', 0
insert into orders_delivered_sta select 2,1000,'01/10/2006', 0
insert into orders_delivered_sta select 3,1000,'09/13/2011', 0
insert into orders_delivered_sta select 4,1001,'01/19/2010', 0
insert into orders_delivered_sta select 5,1001,'02/21/2011', 0
insert into orders_delivered_sta select 6,1002,'02/11/2009', 0
insert into orders_delivered_sta select 7,1002,'08/27/2010', 0
insert into orders_delivered_sta select 8,1003,'07/15/2012', 0
insert into orders_delivered_sta select 9,1004,'03/09/2007', 0
insert into orders_delivered_sta select 10,1010,'10/01/2010', 0
insert into orders_delivered_sta select 11,1011,'03/27/2011', 0
insert into orders_delivered_sta select 12,1012,'07/25/2010', 0
insert into orders_delivered_sta select 13,1013,'09/18/2004', 0

Answer 1

You could use a CTE and a window MAX():
;
WITH max_dates AS (
SELECT
*,
max_date = MAX(date) OVER (PARTITION BY orders_delivered_id)
FROM orders_delivered_sta
WHERE orders_delivered_id IN (SELECT orders_delivered_id FROM orders_delivered)
)
UPDATE max_dates
SET now_ind = 1
WHERE date = max_date
References:
WITH common_table_expression (Transact-SQL)
OVER Clause (Transact-SQL)

Answer 2

This is the query in MySQL, but translating it to SQL-Server should be straight forward as I am using plain SQL. Notice I have changed the date to be in a different form (YYYY-MM-DD) to avoid castings from string to date.
update t3
set t3.now_ind = 1
where t3.orders_delivered_sta_id in (
select distinct t1.orders_delivered_sta_id from t1
left join (
select t2.orders_delivered_id, max(t2.adate) as MaxDate from t2
group by t2.orders_delivered_id
) t2 on (t1.orders_delivered_id = t2.orders_delivered_id) and (t1.adate = t2.MaxDate)
where t2.orders_delivered_id is not null
) and exists (
select * from o1
join od1 on (o1.order_id = od1.orders_delivered_id)
where (t3.orders_delivered_id = od1.orders_id)
)
Here is an example
Hope this helps
PS: You did need those 3 tables... I'll read questions better next time :)

Answer 3

Try this:
UPDATE orders_delivered_sta
SET now_ind = 1
WHERE orders_delivered_sta_id IN(
SELECT orders_delivered_sta_id
FROM (
SELECT orders_delivered_sta_id,
ROW_NUMBER() OVER(PARTITION BY orders_delivered_id ORDER BY date DESC) AS num
FROM orders_delivered_sta) AS T
WHERE T.num = 1)