For example there is some table with below data:
No Id Value
1 100 1
2 100 0
3 100 1
4 100 2
1 101 1
2 101 2
1 102 0
2 102 1
I have to write SQL query, which will return row count based on specific condition. If the value matches 0 then need to reset running counts and start from 1 and make previous row values as 0
So the result will be like:
No Id Value Running Count
1 100 1 0
2 100 0 0
3 100 1 1
4 100 1 2
1 101 1 1
2 101 2 2
1 102 1 0
2 102 0 0
Your sample dataset is quite limited so I'm not sure of all edge cases but see if the following works for you. If not it might help get you there.
This gets a running count using a window & case expression and uses lead to check the next value.
If the current value or next value is 0 the count is 0, otherwise it's the running count subtracting 1 if there is a 0 in the Id block indicating the count was reset.
select No, Id, Value,
case when value = 0 or nv = 0
then 0
else
rc - case when Min(value) over(partition by id) = 0 then 1 else 0 end
end Running_Count
from (
select *,
Sum(case when value = 0 then 0 else 1 end) over(partition by id order by no) rc,
Lead(Value) over(partition by Id order by No)nv
from t
)t;
Related
I want to count the number of rows between polarity changes grouped by id in SQL. I'm thinking that there may be a clever way to use window functions to get the job done but I don't know what it is.
Consider data like this:
id
polarity
date
1
0
12/1
1
1
12/2
1
0
12/3
1
0
12/4
1
1
12/5
2
0
12/1
2
0
12/2
2
0
12/3
2
1
12/4
2
0
12/5
2
0
12/6
2
0
12/7
2
1
12/8
Is there a way to count the number of rows between each change in polarity to get something like this :
id
n
1
1
1
2
2
3
2
3
You can do:
select id, count(*) as n
from (
select *,
sum(i) over(partition by id order by date) as g
from (
select *, case when polarity <> lag(polarity)
over(partition by id order by date)
then 1 else 0 end as i
from t
) x
) y
group by id, g
having max(polarity) = 0
I have data as below where for one customer ID there are several orders (KEY) which is the primary key. I have also have a activity flag as below (either 0 or 1).
CUST_ID KEY FLAG
1 1 1
1 2 1
1 3 1
1 4 0
1 5 0
1 6 1
1 7 1
1 8 0
1 9 0
Now I want to create ranks as below based on the FLAG. The idea is to give same Rank as preceding row if the FLAG is same as preceding row. The Rank increments if the current value is different from preceding value.
CUST_ID KEY FLAG RN
1 1 1 1
1 2 1 1
1 3 1 1
1 4 0 2
1 5 0 2
1 6 1 3
1 7 1 3
1 8 0 4
1 9 0 4
I'm new to SQL, so please let me know if I need to reframe my question.
Use LAG() window function to get each row's previous flag and then use SUM() window function to create the rankings:
SELECT CUST_ID, KEY, FLAG,
SUM(CASE WHEN FLAG <> prev_FLAG THEN 1 END) OVER (PARTITION BY CUST_ID ORDER BY KEY) RN
FROM (
SELECT *, LAG(FLAG, 1, FLAG - 1) OVER (PARTITION BY CUST_ID ORDER BY KEY) prev_FLAG
FROM tablename
) t;
See the demo.
The code could be simplified, depending on the specific database that you use.
I have a table with Scenario,Product,AlgoKey,User Select,System Select columns, I have to select the algo key for each scenario, The first priority goes to user selected otherwise system selected.
I have Shared my Inout & output result below, could you please help me how to write query for this.
Scenario
Product
AlgoKey
User Select
SystemSelect
1
P101
1
0
1
1
P102
2
1
0
2
P101
1
0
1
2
P102
2
0
0
3
P101
1
1
1
3
P102
2
0
0
4
P101
1
0
0
4
P102
2
0
1
OutPut :
Scenario
AlgoKey
Columnselected
1
2
User
2
1
System
3
1
User
4
2
System
here is how you can do it
select scenario , AlgoKey, case when Userselect = 1 then 'User' else 'System' end Columnselected
from (
select *, ROW_NUMBER() over (partition by scenario,productkey order by userselect desc, systemselect desc) rn
from tableName
) t
where rn = 1
Consider the table ordered by id with column IsSatisfied.
ID
IsSatisfied
1
0
2
1
3
0
4
0
5
1
6
0
....
...
I would like to create another column State, that initially takes value 0 and changes it between 0 and 1, only when the value of Isatisfied is equal to 1, as in the table below.
ID
IsSatisfied
State
1
0
0
2
1
1
3
0
1
4
0
1
5
1
0
6
0
0
....
...
...
I tried LAG() function or recursive CTE, but unfortunately failed.
The closest solution that I have found is Conditional Recursive SQL Select, but I was not able to convert it to suit my needs.
If I understand correctly, you want a cumulative sum of issatisfied -- and then the remainder when divided by 2:
select t.*,
( sum(issatisfied) over (order by id) % 2 ) as state
from t;
Have the following table tblTrans where
Trans_ID Trans Sequence Trans_PointsEarned Trans_PointsApplied
4452 1 1 1
4452 2 1 1
4452 3 0 1
4462 1 1 1
4462 2 1 1
4462 3 1 1
4462 4 1 1
4462 5 1 1
9101 1 0 1
9101 2 0 1
9101 3 0 1
9101 4 0 1
(useless table doesnt work)
I need to set the following on another field per every customer ID.
So Customer_OverallPoints
4452 = 2 (doesn't count 0's)
4462 = 4 (I want to cap the points to 4 based on the sequence and transID and customerID)
9101 = 0 (dont count 0's).
This needs to be applied to thousands of records based on customerID and TransID where Trans_Sequence is within the same Trans_ID and it only counts the first 4 rows that have the Trans_pointsEarned = 1.
I tried putting a psuedocode together but it just looked ridicilous and I can't even come up with the logic for this.
Thanks
Assuming that TransId is really the customer id, I think the basic logic is just an aggregation:
select t.TransId,
(case when sum(t.Trans_PointsEarned) > 4 then 4
else sum(t.Trans_PointsEarned)
end) as Customer_OverallPoints
from tblTrans t
group by t.TransId;
You can put this into an update statement as:
update customers c
set Customer_OverallPoints = (select (case when sum(t.Trans_PointsEarned) > 4 then 4
else sum(t.Trans_PointsEarned)
end)
from tblTrans t
where t.TransId = c.CustomerId
);