I am working on the problem where I have to get the count of streak with max value, but to get the exact result I have to count that point as well where the streak breaks. My table looks like this
+-----------------+--------+-------+
| customer_number | Months | Flags |
+-----------------+--------+-------+
| 1 | 12 | 1 |
| 1 | 1 | 1 |
| 1 | 2 | 1 |
| 1 | 3 | 1 |
| 1 | 4 | 1 |
| 1 | 5 | 1 |
| 1 | 8 | 1 |
| 1 | 9 | 1 |
| 1 | 10 | 1 |
| 1 | 11 | 1 |
| 6 | 12 | 1 |
| 6 | 1 | 1 |
| 6 | 2 | 1 |
| 6 | 3 | 1 |
| 6 | 4 | 1 |
| 6 | 5 | 4 |
| 6 | 9 | 1 |
| 6 | 10 | 1 |
| 6 | 11 | 1 |
| 7 | 5 | 1 |
| 8 | 9 | 1 |
| 8 | 10 | 1 |
| 8 | 11 | 1 |
| 9 | 9 | 1 |
| 9 | 10 | 1 |
| 9 | 11 | 1 |
| 10 | 11 | 1 |
+-----------------+--------+-------+
and my desired output is
+----------+--------------------+
| Customer | Consecutive streak |
+----------+--------------------+
| 1 | 10 |
| 6 | 6 |
| 7 | 1 |
| 8 | 3 |
| 9 | 3 |
| 10 | 1 |
+----------+--------------------+
the code I have
SELECT customer_number, max(streak) max_consecutive_streak FROM (
SELECT customer_number, COUNT(*) as streak
FROM
(select *,
(row_number() over (order by customer_number) -
row_number() over (order by customer_number)
) as counts
from table1
) cc
group by customer_number, counts
)
GROUP BY 1;
It is working good but for customer_number 6 it returns 5 but I want it to be 6, means it should count 4 as well in its longest streak as the streak breaks at this point. Any idea how can I achieve that?
You can use a cte with row_number:
with cte(r, id, flag) as (
select row_number() over (order by c.customer_number), c.* from customers c
),
freq(id, t, f) as (
select c2.id, c2.f, count(*) from
(select c.id, (select sum(c1.flag!=c.flag) from cte c1 where c1.id=c.id and c1.r <= c.r) f from cte c)
c2 group by c2.id, c2.f
)
select id, max(f) from freq group by id;
While going through SQL columns, if we find text match "NEW" in Calc column, update the incrementing a count starting with 1 in Results column.
It should look like this on the output:
The following uses an id column to resolve the order issue. Replace that with your corresponding expression. This also addresses the requirement to start the display sequence with 1 and also show 0 for the 'NEW' rows.
The SQL (updated):
SELECT logs.*
, CASE WHEN text = 'NEW' THEN 0
ELSE
COALESCE(SUM(CASE WHEN text = 'NEW' THEN 1 END) OVER (PARTITION BY xrank ORDER BY id)+1, 1)
END AS display
FROM logs
ORDER BY id
The result:
+----+-------+------+---------+
| id | xrank | text | display |
+----+-------+------+---------+
| 1 | 1 | A | 1 |
| 2 | 1 | B | 1 |
| 3 | 1 | C | 1 |
| 4 | 1 | NEW | 0 |
| 5 | 1 | D | 2 |
| 6 | 1 | Q | 2 |
| 7 | 1 | B | 2 |
| 8 | 1 | NEW | 0 |
| 9 | 1 | D | 3 |
| 10 | 1 | Z | 3 |
| 11 | 2 | A | 1 |
| 12 | 2 | B | 1 |
| 13 | 2 | C | 1 |
| 14 | 2 | NEW | 0 |
| 15 | 2 | D | 2 |
| 16 | 2 | Q | 2 |
| 17 | 2 | B | 2 |
| 18 | 2 | NEW | 0 |
| 19 | 2 | D | 3 |
| 20 | 2 | Z | 3 |
+----+-------+------+---------+
You need a column that specifies the ordering for the table. With that, just use a cumulative sum:
select t.*,
1 + sum(case when Calc = 'NEW' then 1 else 0 end) over (partition by Rank_Id order by Seq) as display
from t;
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I currently have a table with transactions that are sequentially ordered for each group like so:
| transaction_no | value |
|----------------|-------|
| 1 | 8 |
| 2 | 343 |
| 3 | 28 |
| 4 | 102 |
| 1 | 30 |
| 2 | 5 |
| 3 | 100 |
| 1 | 12 |
| 2 | 16 |
| 3 | 28 |
| 4 | 157 |
| 5 | 125 |
However I'm interested in add another column that assigns a unique ID to each
grouping (set of transactions where the transaction_no starts with 1 and ends with x
where the transaction_no immediately after x is 1). So the goal is a table like this:
| transaction_no | value | stmt_id |
|----------------|-------|---------|
| 1 | 8 | 1001 |
| 2 | 343 | 1001 |
| 3 | 28 | 1001 |
| 4 | 102 | 1001 |
| 1 | 30 | 1002 |
| 2 | 5 | 1002 |
| 3 | 100 | 1002 |
| 1 | 12 | 1003 |
| 2 | 16 | 1003 |
| 3 | 28 | 1003 |
| 4 | 157 | 1003 |
| 5 | 125 | 1003 |
How would I do this?
This is a variation of the gaps-and-island problem. For it to be solvable, as commented by Gordon Linoff, you need a column that can be used to order the rows. I assume that such a column exists and is called id.
The typical solution involves ranking the records and performing a window sum. When the difference between the overal rank and the window sum changes, a new group starts.
Consider the following query:
select
id,
transaction,
value,
1000
+ rn
- sum(case when transaction_no = lag_transaction_no + 1 then 1 else 0 end)
over(order by id) grp
from (
select
t.*,
row_number() over(order by id) rn,
lag(transaction_no) over(order by id) lag_transaction_no
from mytable t
) t
With this sample data:
id | transaction_no | value
-: | -------------: | ----:
1 | 1 | 8
2 | 2 | 343
3 | 3 | 28
4 | 4 | 102
5 | 1 | 30
6 | 2 | 5
7 | 3 | 100
8 | 1 | 12
9 | 2 | 16
10 | 3 | 28
11 | 4 | 157
12 | 5 | 125
The query returns:
id | transaction_no | value | grp
-: | -------------: | ----: | ---:
1 | 1 | 8 | 1001
2 | 2 | 343 | 1001
3 | 3 | 28 | 1001
4 | 4 | 102 | 1001
5 | 1 | 30 | 1002
6 | 2 | 5 | 1002
7 | 3 | 100 | 1002
8 | 1 | 12 | 1003
9 | 2 | 16 | 1003
10 | 3 | 28 | 1003
11 | 4 | 157 | 1003
12 | 5 | 125 | 1003
Demo on SQL Server 2012 DB Fiddle
I'm using SQL Server 2014 and i'm having a trouble with a query.
I have this scenario bellow:
| Number | Series | Name |
|--------|--------|---------|
| 9 | 1 | Name 1 |
| 5 | 3 | Name 2 |
| 8 | 2 | Name 3 |
| 7 | 3 | Name 4 |
| 0 | 1 | Name 5 |
| 1 | 2 | Name 6 |
| 9 | 2 | Name 7 |
| 3 | 3 | Name 8 |
| 4 | 1 | Name 9 |
| 0 | 1 | Name 10 |
and I need to get it ordered by series column like this:
| Number | Series | Name |
|--------|--------|---------|
| 9 | 1 | Name 1 |
| 8 | 2 | Name 3 |
| 5 | 3 | Name 2 |
| 7 | 1 | Name 5 |
| 1 | 2 | Name 6 |
| 0 | 3 | Name 4 |
| 4 | 1 | Name 9 |
| 9 | 2 | Name 7 |
| 3 | 3 | Name 8 |
| 0 | 1 | Name 10 |
Actually is more a sequency in "series" column than an ordenation.
1,2,3 again 1,2,3...
Somebody could help me?
You can do this using the ANSI standard function row_number():
select number, series, name
from (select t.*, row_number() over (partition by series order by number) as seqnum
from t
) t
order by seqnum, series;
This assigns "1" to the first record for each series, "2" to the second, and so on. The outer order by then puts all the "1"s together, all the "2" together. This has the effect of interleaving the values of the series.
thank you for attention.
I have a table called "PROD_COST" with 5 fields
(ID,Duration,Cost,COST_NEXT,COST_CHANGE).
I need extra field called "groups" for aggregation.
Duration = number of days the price is valid (1 day=1row).
Cost = product price in this day.
Cost_next = lead(cost,1,0).
Cost_change = Cost_next - Cost.
Now i need to group by Cost_change. It can be
positive,negative or 0 values.
+----+---+------+------+------+
| 1 | 1 | 10 | 8,5 | -1,5 |
| 2 | 1 | 8,5 | 12,2 | 3,7 |
| 3 | 1 | 12,2 | 5,3 | -6,9 |
| 4 | 1 | 5,3 | 4,2 | 1,2 |
| 5 | 1 | 4,2 | 6,2 | 2 |
| 6 | 1 | 6,2 | 9,2 | 3 |
| 7 | 1 | 9,2 | 7,5 | -2,7 |
| 8 | 1 | 7,5 | 6,2 | -1,3 |
| 9 | 1 | 6,2 | 6,3 | 0,1 |
| 10 | 1 | 6,3 | 7,2 | 0,9 |
| 11 | 1 | 7,2 | 7,5 | 0,3 |
| 12 | 1 | 7,5 | 0 | 7,5 |
+----+---+------+------+------+`
I need to make a query, which will group it by first negative or positive value (+ - + - + -). Last one field is what i want.
Sorry for my English `
+----+---+------+------+------+---+
| 1 | 1 | 10 | 8,5 | -1,5 | 1 |
| 2 | 1 | 8,5 | 12,2 | 3,7 | 2 |
| 3 | 1 | 12,2 | 5,3 | -6,9 | 3 |
| 4 | 1 | 5,3 | 4,2 | 1,2 | 4 |
| 5 | 1 | 4,2 | 6,2 | 2 | 4 |
| 6 | 1 | 6,2 | 9,2 | 3 | 4 |
| 7 | 1 | 9,2 | 7,5 | -2,7 | 5 |
| 8 | 1 | 7,5 | 6,2 | -1,3 | 5 |
| 9 | 1 | 6,2 | 6,3 | 0,1 | 6 |
| 10 | 1 | 6,3 | 7,2 | 0,9 | 6 |
| 11 | 1 | 7,2 | 7,5 | 0,3 | 6 |
| 12 | 1 | 7,5 | 0 | 7,5 | 6 |
+----+---+------+------+------+---+`
If you're in SQL Server 2012 you can use the window functions to do this:
select
id, COST_CHANGE, sum(GRP) over (order by id asc) +1
from
(
select
*,
case when sign(COST_CHANGE) != sign(isnull(lag(COST_CHANGE)
over (order by id asc),COST_CHANGE)) then 1 else 0 end as GRP
from
PROD_COST
) X
Lag will get the value from previous row, check the sign of it and compare it to the current row. If the values don't match, the case will return 1. The outer select will do a running total of these numbers, and every time there is 1, it will increase the total.
It is possible to use the same logic with older versions too, you'll just have to fetch the previous row from the table using the id and do running total by re-calculating all rows before the current one.
Example in SQL Fiddle
James's answer is close but it doesn't handle the zero value correctly. This is a pretty easy modification. One tricky approximation uses differences between product changes:
select id, COST_CHANGE, sum(IsNewGroup) over (order by id asc) +1
from (select pc.*,
(case when sign(cost_change) - sign(lag(cost_change) over (order by id)) between -1 and 1
then 0
else 1 -- `NULL` intentionally goes here
end) IsNewGroup
from Prod_Cost
) pc
For clarity, here is a SQL Fiddle with zero values. From my understanding of the question, the OP only wants an actual sign change.
This may still not be correct. The OP simply is not clear about what to do about 0 values.