Im fairly new to SQL.
I have a table called Entity and that Entity have 4 columns, id, valone, valtwo, valthree.
What Im trying to accomplish is sum valone with valtwo and check if that SUM is less than valthree.
So we have SUM(valone + valtwo)
and check WHERE SUM(valone + valtwo) < valthree.
How can I accomplish this?
SUM is an aggregation function, and not what you need here. You need a row by row function, which is simply +:
SELECT *, valone + valtwo
FROM dbo.Entity
WHERE valone + valtwo < valthree
;
Related
Have a query that uses double select (with select max) to fetch the row with the latest 'calculation_time' column among multiple rows which can have the same 'patient_set_id'. If there are multiple rows with the same 'patient_set_id', only the row with the latest 'calculation_time' should be retrieved. Calculation time is a date.
So far I've tried this but I'm not really sure if there is any better way for this, maybe using ORDER BY. But I'm very new to sql and need to know which one would be the fastest and more appropriate?
SELECT median from diagnostic_risk_stats WHERE
calculation_time=(SELECT MAX(calculation_time) FROM diagnostic_risk_stats WHERE
patient_set_id = UNHEX(REPLACE('5a9dbfca-74d6-471a-af27-31beb4b53bb2', "-","")));
You can use not exists as follows:
SELECT median
from diagnostic_risk_stats t
WHERE not exists
(Select 1 from diagnostic_risk_stats tt
Where t.patient_set_id = tt.patient_set_id
And tt.calculation_time > t.calculation_time)
And t.patient_set_id = UNHEX(REPLACE('5a9dbfca-74d6-471a-af27-31beb4b53bb2', "-",""));
Consider that I have a table with one column "A" and I would like to create another column called "B" such that
B[i] = 0.2*A[i] + 0.8*B[i-1]
where B[0]=0.
My problem is that I cannot use the OVER() function because I want to use the values in B while I am trying to construct B. Any idea would be appreciated. Thanks
This is a rather complex mathematical exercise. You want to accumulate exponentially decreasing amounts from previous rows.
It is a little confusing because the amount going in on each row is 20%, but that is just a factor in the formula.
In any case, this seems to do what you want:
select t.*,
sum(power(0.8, -n) * a * 0.2) over (order by id) / power(0.8, -n)
from (select t.8,
row_number() over (order by id) - 1 as n
from t
) x;
Here is a db<>fiddle using Postgres.
I'm currently working on calculating a larger set of data with a number of joins and the end result is a calculation across two tables. My current script looks like the following:
USE db1
Go
SELECT
customer, tb1.custid
FROM
[dbo].[tb1]
LEFT OUTER JOIN
[dbo].[tb2] ON tb1.custid = tb2.custid
LEFT OUTER JOIN
[dbo].[tb3] ON tb2.custnumber = tb3.custnumber
LEFT OUTER JOIN
[dbo].[tb4] ON tb2.custid = tb4.custid
WHERE
tb1.custclass = 'non-person'
AND tb4.zip IN ('11111', '11112')
GO
As you can see, it's not the cleanest, but it's working for gathering initial information. The reasoning for the number of joins is due to an incredibly odd table structure I did not create and the fact that the numerical data I need is only stored in tb3.
What I'm now trying to do is calculate the sum of 3 fields from tb3 that are all set as numeric fields and do an AND/OR comparison against a 4th field (also numeric). I know I can SUM them together, but I'm hoping for some input on three things:
Where to place that SUM calculation in the query?
Where to place and how to do the comparison of the SUM total against the 4th field?
Is it possible to return the higher of the two values to a TOTAL column in the initial SELECT?
Thank you in advance.
Where to place that SUM calculation in the query?
If you want it output, you probably want to just add it to the SELECT
SELECT
customer, tb1.custid
(tb3.col1 + tb3.col2 + tb3.col3) as Sum
FROM
...
Where to place and how to do the comparison of the SUM total against the 4th field?
You probably want to do this with a CASE statement, and this also answers your last question
Is it possible to return the higher of the two values to a TOTAL column in the initial SELECT?
SELECT
customer, tb1.custid
CASE WHEN (tb3.col1 + tb3.col2 + tb3.col3) > tb3.col4
THEN (tb3.col1 + tb3.col2 + tb3.col3)
ELSE tb3.col4
END as Total
FROM
...
You should be able to calculate the sum as a nested query:
SELECT (field1 + field2 + field3) AS fields_sum FROM tb3 (...)
Then in your main query you could do something like:
SELECT customer, tb1.custid, (CASE WHEN fields_sum > fourth_field THEN fields_sum ELSE fourth_field END) AS TOTAL (...)
I have this query but I'm getting two columns of houseid:
How do I only get one?
SELECT vehv2pub.houseid, vehv2pub.vehid, vehv2pub.epatmpg,
dayv2pub.houseid, dayv2pub.trpmiles
FROM vehv2pub, dayv2pub
WHERE vehv2pub.vehid >= 1
AND dayv2pub.trpmiles < 15
AND dayv2pub.houseid = vehv2pub.houseid;
And also, how do I get the average of the epatmpg? So the query would just return the value?
The most elegant way would be to use the USING clause in an explicit join condition:
SELECT houseid, v.vehid, v.epatmpg, d.houseid, d.trpmiles
FROM vehv2pub v
JOIN dayv2pub d USING (houseid)
WHERE v.vehid >= 1
AND d.trpmiles < 15;
This way, the column houseid is in the result only once, even if you use SELECT *.
Per documentation:
USING is a shorthand notation: it takes a comma-separated list of
column names, which the joined tables must have in common, and forms a
join condition specifying equality of each of these pairs of columns.
Furthermore, the output of JOIN USING has one column for each of the
equated pairs of input columns, followed by the remaining columns from each table.
To get the average epatmpg for the selected rows:
SELECT avg(v.epatmpg) AS avg_epatmpg
FROM vehv2pub v
JOIN dayv2pub d USING (houseid)
WHERE v.vehid >= 1
AND d.trpmiles < 15;
If there are multiple matches in dayv2pub, the derived table can hold multiple instances of each row in vehv2pub after the join. avg() is based on the derived table.
not 100% sure this works in postgres sql, but something like this gets the average in SQL server:
SELECT vehv2pub.houseid, avg(vehv2pub.epatmpg)
FROM vehv2pub, dayv2pub
WHERE vehv2pub.vehid >= 1
AND dayv2pub.trpmiles < 15
AND dayv2pub.houseid = vehv2pub.houseid
GROUP BY vehv2pub.houseid
I need to calculate the net total of a column-- sounds simple. The problem is that some of the values should be negative, as are marked in a separate column. For example, the table below would yield a result of (4+3-5+2-2 = 2). I've tried doing this with subqueries in the select clause, but it seems unnecessarily complex and difficult to expand when I start adding in analysis for other parts of my table. Any help is much appreciated!
Sign Value
Pos 4
Pos 3
Neg 5
Pos 2
Neg 2
Using a CASE statement should work in most versions of sql:
SELECT SUM( CASE
WHEN t.Sign = 'Pos' THEN t.Value
ELSE t.Value * -1
END
) AS Total
FROM YourTable AS t
Try this:
SELECT SUM(IF(sign = 'Pos', Value, Value * (-1))) as total FROM table
I am adding rows from a single field in a table based on values from another field in the same table using oracle 11g as database and sql developer as user interface.
This works:
SELECT COUNTRY_ID, SUM(
CASE
WHEN ACCOUNT IN 'PTBI' THEN AMOUNT
WHEN ACCOUNT IN 'MLS_ENT' THEN AMOUNT
WHEN ACCOUNT IN 'VAL_ALLOW' THEN AMOUNT
WHEN ACCOUNT IN 'RSC_DEV' THEN AMOUNT * -1
END) AS TI
FROM SAMP_TAX_F4
GROUP BY COUNTRY_ID;
select a= sum(Value) where Sign like 'pos'
select b = sum(Value) where Signe like 'neg'
select total = a-b
this is abit sql-agnostic, since you didnt say which db you are using, but it should be easy to adapat it to any db out there.