I'd like to check if a column in a table has values with a small number of value counts.
Consider the following table as an example:
RowID |Product
1 | A
2 | A
3 | B
...
200.000 | C
the following table is aggregated of the table above:
Product |Count
A |204
B |682
C |553
D |1402
E |30855
F |357
G |1
H |542
What I'd like to know of the column Product of my table is, whether or not a Product has a count that is less than 5%. And if so, the SQL statement should return: 'Some values of this field have a small number of value counts'
In other words: IF [MinValueCount]/[Count] <= .05 then 'Some values of this field have a small number of value counts' else 'null'
With the example above, I should get: 'Some values of this field have a small number of value counts'
as product G is less than 5% of the total count of products.
how should the SQL statement look like?
With kind regards,
Lazzanova
Use two levels of aggregation. You can get the total using window functions:
select max( 'Some values of this field have a small number of value counts')
from (select product, count(*) as cnt,
sum(count(*)) over () as total_cnt
from t
) t
where cnt < 0.05 * total_cnt;
The use of max() in the outer query is just to return one row. You could also use fetch or a similar clause (whatever your database supports):
select 'Some values of this field have a small number of value counts'
from (select product, count(*) as cnt,
sum(count(*)) over () as total_cnt
from t
) t
where cnt < 0.05 * total_cnt
fetch first 1 row only;
Related
I have a table with data like this (acc_v in query):
value
id
100
1
300
2
200
1
As you can see there are multiple values per id. I want to sum all of the values across the ids and end up with this:
value
id
300
1
300
2
;with accV as (SELECT
d_id
,[period_end_date]
,max(a_value) as value
,id
FROM bh
where period_end_date = '2021-6-30'
group by d_id, period_end_date, id)
SELECT bh.id, sum(value)
FROM bh join accV on accV.id = bh.id
group by bh.id
For some reason the total values are adding up to significantly larger amounts than they should be. I verified this by taking the original values and summing them in excel. If anyone knows what I am doing wrong the help is much appreciated.
You can use window functions:
select id, sum(sum(value)) over () as total_sum
from t
group by id;
Imagine a table with only one column.
+------+
| v |
+------+
|0.1234|
|0.8923|
|0.5221|
+------+
I want to do the following for row K:
Take row K=1 value: 0.1234
Count how many values in the rest of the table are less than or equal to value in row 1.
Iterate through all rows
Output should be:
+------+-------+
| v |output |
+------+-------+
|0.1234| 0 |
|0.8923| 2 |
|0.5221| 1 |
+------+-------+
Quick Update I was using this approach to compute a statistic at every value of v in the above table. The cross join approach was way too slow for the size of data I was dealing with. So, instead I computed my stat for a grid of v values and then matched them to the vs in the original data. v_table is the data table from before and stat_comp is the statistics table.
AS SELECT t1.*
,CASE WHEN v<=1.000000 THEN pr_1
WHEN v<=2.000000 AND v>1.000000 THEN pr_2
FROM v_table AS t1
LEFT OUTER JOIN stat_comp AS t2
Windows functions were added to ANSI/ISO SQL in 1999 and to to Hive in version 0.11, which was released on 15 May, 2013.
What you are looking for is a variation on rank with ties high which in ANSI/ISO SQL:2011 would look like this-
rank () over (order by v with ties high) - 1
Hive currently does not support with ties ... but the logic can be implemented using count(*) over (...)
select v
,count(*) over (order by v) - 1 as rank_with_ties_high_implicit
from mytable
;
or
select v
,count(*) over
(
order by v
range between unbounded preceding and current row
) - 1 as rank_with_ties_high_explicit
from mytable
;
Generate sample data
select 0.1234 as v into #t
union all
select 0.8923
union all
select 0.5221
This is the query
;with ct as (
select ROW_NUMBER() over (order by v) rn
, v
from #t ot
)
select distinct v, a.cnt
from ct ot
outer apply (select count(*) cnt from ct where ct.rn <> ot.rn and v <= ot.v) a
After seeing your edits, it really does look look like you could use a Cartesian product, i.e. CROSS JOIN here. I called your table foo, and crossed joined it to itself as bar:
SELECT foo.v, COUNT(foo.v) - 1 AS output
FROM foo
CROSS JOIN foo bar
WHERE foo.v >= bar.v
GROUP BY foo.v;
Here's a fiddle.
This query cross joins the column such that every permutation of the column's elements is returned (you can see this yourself by removing the SUM and GROUP BY clauses, and adding bar.v to the SELECT). It then adds one count when foo.v >= bar.v, yielding the final result.
You can take the full Cartesian product of the table with itself and sum a case statement:
select a.x
, sum(case when b.x < a.x then 1 else 0 end) as count_less_than_x
from (select distinct x from T) a
, T b
group by a.x
This will give you one row per unique value in the table with the count of non-unique rows whose value is less than this value.
Notice that there is neither a join nor a where clause. In this case, we actually want that. For each row of a we get a full copy aliased as b. We can then check each one to see whether or not it's less than a.x. If it is, we add 1 to the count. If not, we just add 0.
I have three columns, all consisting of 1's and 0's. For each of these columns, how can I calculate the percentage of people (one person is one row/ id) who have a 1 in the first column and a 1 in the second or third column in oracle SQL?
For instance:
id marketing_campaign personal_campaign sales
1 1 0 0
2 1 1 0
1 0 1 1
4 0 0 1
So in this case, of all the people who were subjected to a marketing_campaign, 50 percent were subjected to a personal campaign as well, but zero percent is present in sales (no one bought anything).
Ultimately, I want to find out the order in which people get to the sales moment. Do they first go from marketing campaign to a personal campaign and then to sales, or do they buy anyway regardless of these channels.
This is a fictional example, so I realize that in this example there are many other ways to do this, but I hope anyone can help!
The outcome that I'm looking for is something like this:
percentage marketing_campaign/ personal campaign = 50 %
percentage marketing_campaign/sales = 0%
etc (for all the three column combinations)
Use count, sum and case expressions, together with basic arithmetic operators +,/,*
COUNT(*) gives a total count of people in the table
SUM(column) gives a sum of 1 in given column
case expressions make possible to implement more complex conditions
The common pattern is X / COUNT(*) * 100 which is used to calculate a percent of given value ( val / total * 100% )
An example:
SELECT
-- percentage of people that have 1 in marketing_campaign column
SUM( marketing_campaign ) / COUNT(*) * 100 As marketing_campaign_percent,
-- percentage of people that have 1 in sales column
SUM( sales ) / COUNT(*) * 100 As sales_percent,
-- complex condition:
-- percentage of people (one person is one row/ id) who have a 1
-- in the first column and a 1 in the second or third column
COUNT(
CASE WHEN marketing_campaign = 1
AND ( personal_campaign = 1 OR sales = 1 )
THEN 1 END
) / COUNT(*) * 100 As complex_condition_percent
FROM table;
You can get your percentages like this :
SELECT COUNT(*),
ROUND(100*(SUM(personal_campaign) / sum(count(*)) over ()),2) perc_personal_campaign,
ROUND(100*(SUM(sales) / sum(count(*)) over ()),2) perc_sales
FROM (
SELECT ID,
CASE
WHEN SUM(personal_campaign) > 0 THEN 1
ELSE 0
end AS personal_campaign,
CASE
WHEN SUM(sales) > 0 THEN 1
ELSE 0
end AS sales
FROM the_table
WHERE ID IN
(SELECT ID FROM the_table WHERE marketing_campaign = 1)
GROUP BY ID
)
I have a bit overcomplicated things because your data is still unclear to me. The subquery ensures that all duplicates are cleaned up and that you only have for each person a 1 or 0 in marketing_campaign and sales
About your second question :
Ultimately, I want to find out the order in which people get to the
sales moment. Do they first go from marketing campaign to a personal
campaign and then to sales, or do they buy anyway regardless of these
channels.
This is impossible to do in this state because you don't have in your table, either :
a unique row identifier that would keep the order in which the rows were inserted
a timestamp column that would tell when the rows were inserted.
Without this, the order of rows returned from your table will be unpredictable, or if you prefer, pure random.
I have the following table which contains ID's and UserId's.
ID UserID
1111 11
1111 300
1111 51
1122 11
1122 22
1122 3333
1122 45
I'm trying to count the distinct number of 'IDs' so that I get a total, but I also need to get a total of ID's that have also seen the that particular ID as well... To get the ID's, I've had to perform a subquery within another table to get ID's, I then pass this into the main query... Now I just want the results to be displayed as follows.
So I get a Total No for ID and a Total Number for Users ID - Also would like to add another column to get average as well for each ID
TotalID Total_UserID Average
2 7 3.5
If Possible I would also like to get an average as well, but not sure how to calculate that. So I would need to count all the 'UserID's for an ID add them altogether and then find the AVG. (Any Advice on that caluclation would be appreciated.)
Current Query.
SELECT DISTINCT(a.ID)
,COUNT(b.UserID)
FROM a
INNER JOIN b ON someID = someID
WHERE a.ID IN ( SELECT ID FROM c WHERE GROUPID = 9999)
GROUP BY a.ID
Which then Lists all the IDs and COUNT's all the USERID.. I would like a total of both columns. I've tried warpping the query in a
SELECT COUNT(*) FROM (
but this only counts the ID's which is great, but how do I count the USERID column as well
You seem to want this:
SELECT COUNT(DISTINCT a.ID), COUNT(b.UserID),
COUNT(b.UserID) * 1.0 / COUNT(DISTINCT a.ID)
FROM a INNER JOIN
b
ON someID = someID
WHERE a.ID IN ( SELECT ID FROM c WHERE GROUPID = 9999);
Note: DISTINCT is not a function. It applies to the whole row, so it is misleading to put an expression in parentheses after it.
Also, the GROUP BY is unnecessary.
The 1.0 is because SQL Server does integer arithmetic and this is a simple way to convert a number to a decimal form.
You can use
SELECT COUNT(DISTINCT a.ID) ...
to count all distinct values
Read details here
I believe you want this:
select TotalID,
Total_UserID,
sum(Total_UserID+TotalID) as Total,
Total_UserID/TotalID as Average
from (
SELECT (DISTINCT a.ID) as TotalID
,COUNT(b.UserID) as Total_UserID
FROM a
INNER JOIN b ON someID = someID
WHERE a.ID IN ( SELECT ID FROM c WHERE GROUPID = 9999)
) x
I have a little problem.
My table is:
Bill Product ID Units Sold
----|-----------|------------
1 | 10 | 25
1 | 20 | 30
2 | 30 | 11
3 | 40 | 40
3 | 20 | 20
I want to SELECT the product which has sold the most units; in this sample case, it should be the product with ID 20, showing 50 units.
I have tried this:
SELECT
SUM(pv."Units sold")
FROM
"Products" pv
GROUP BY
pv.Product ID;
But this shows all the products, how can I select only the product with the most units sold?
Leaving aside for the moment the possibility of having multiple products with the same number of units sold, you can always sort your results by the sum, highest first, and take the first row:
SELECT pv."Product ID", SUM(pv."Units sold")
FROM "Products" pv
GROUP BY pv."Product ID"
ORDER BY SUM(pv."Units sold") DESC
LIMIT 1
I'm not quite sure whether the double-quote syntax for column and table names will work - exact syntax will depend on your specific RDBMS.
Now, if you do want to get multiple rows when more than one product has the same sum, then the SQL will become a bit more complicated:
SELECT pv.`Product ID`, SUM(pv.`Units sold`)
FROM `Products` pv
GROUP BY pv.`Product ID`
HAVING SUM(pv.`Units sold`) = (
select max(sums)
from (
SELECT SUM(pv2.`Units sold`) as "sums"
FROM `Products` pv2
GROUP BY pv2.`Product ID`
) as subq
)
Here's the sqlfiddle
SELECT SUM(pv."Units sold") as `sum`
FROM "Products" pv
group by pv.Product ID
ORDER BY sum DESC
LIMIT 1
limit 1 + order by
The Best and effective way to this is Max function
Here's The General Syntax of Max function
SELECT MAX(ID) AS id
FROM Products;
and in your Case
SELECT MAX(Units Sold) from products
Here is the Complete Reference to MIN and MAX functions in Query
Click Here