I have a data-set in which there are duplicate IDs in the first column. I'm hoping to obtain a single row of data for each ID based on the second column's value. The data looks like so:
ID Info_Source Prior?
A 1 Y
A 3 N
A 2 Y
B 1 N
B 1 N
B 2 Y
C 2 N
C 3 Y
C 1 N
Specifically the criteria would call for prioritizing based on the second column's value (3 highest priority; then 1; and lastly 2): if the 'Info_Source' column has a value of 3, return that row; if there is no 3 in the second column for a given ID, look for a 1 and if found return that row; and finally if there is no 3 or 1 associated with the ID, search for 2 and return that row for the ID.
The desired results would be a single row for each ID, and the resulting data would be:
ID Info_Source Prior?
A 3 N
B 1 N
C 3 Y
row_number() over() usually solves these needs nicely and efficiently e.g.
select ID, Info_Source, Prior
from (
select ID, Info_Source, Prior
, row_number() over(partition by id order by Info_source DESC) as rn
)
where rn = 1
For prioritizing the second column's value (3 ; then 1, then 2) use a case expression to alter the raw value into an order that you need.
select ID, Info_Source, Prior
from (
select ID, Info_Source, Prior
, row_number() over(partition by id
order by case when Info_source = 3 then 3
when Infor_source = 1 then 2
else 1 end DESC) as rn
)
where rn = 1
Related
I have a pretty lengthy SQL query which I'm going to run on Oracle via hibernate. It consists of two nested selects. In the first select statement, a number of sums are calculated, but in one of them I want to filter the results using unique ids.
SELECT ...
SUM(NVL(CASE WHEN SECOND_STATUS= 50 OR SECOND_STATUS IS NULL THEN RECEIVE_AMOUNT END, 0) +
NVL(CASE WHEN FIRST_STATUS = 1010 THEN AMOUNT END, 0) +
NVL(CASE WHEN FIRST_STATUS = 1030 THEN AMOUNT END, 0) -
NVL(CASE WHEN FIRST_STATUS = 1010 AND (SECOND_STATUS= 50 OR SECOND_STATUS IS NULL) THEN RECEIVE_AMOUNT END, 0)) TOTAL, ...
And at the end:
... FROM (SELECT s.*, p.* FROM FIRST_TABLE s
JOIN SECOND_TABLE p ON s.ID = p.FIRST_ID
In one of the lines that start with NVL (second line actually), I want to add a distinct clause that sums the amounts only if first table ids are unique. But I don't know if this is possible or not. If yes, how would it be?
Assume such setup
select * from first;
ID AMOUNT
---------- ----------
1 10
2 20
select * from second;
SECOND_ID FIRST_ID AMOUNT2
---------- ---------- ----------
1 1 100
2 1 100
3 2 100
After the join you get the total sum of both amounts too high because the amount from the first table is duplicated.
select *
from first
join second on first.id = second.first_id;
ID AMOUNT SECOND_ID FIRST_ID AMOUNT2
---------- ---------- ---------- ---------- ----------
1 10 1 1 100
1 10 2 1 100
2 20 3 2 100
You must add a row_number that identifies the first occurence in the parent table and consider in the AMOUNT only the first row and resets it to NULL in the duplicated rows.
select ID,
case when row_number() over (partition by id order by second_id) = 1 then AMOUNT end as AMOUNT,
SECOND_ID, FIRST_ID, AMOUNT2
from first
join second on first.id = second.first_id;
ID AMOUNT SECOND_ID FIRST_ID AMOUNT2
---------- ---------- ---------- ---------- ----------
1 10 1 1 100
1 2 1 100
2 20 3 2 100
Now you can safely sum in a separate subquery
with tab as (
select ID,
case when row_number() over (partition by id order by second_id) = 1 then AMOUNT end as AMOUNT,
SECOND_ID, FIRST_ID, AMOUNT2
from first
join second on first.id = second.first_id
)
select id, sum(nvl(amount,0) + nvl(amount2,0))
from tab
group by id
;
ID SUM(NVL(AMOUNT,0)+NVL(AMOUNT2,0))
---------- ---------------------------------
1 210
2 120
Note also that this is an answer to your question. Some will argue that in your situation you should first aggregate and than join. This will also resolve your problem possible more elegantly.
Consider, I have the following in a select query:
ID Flag
5 Y
5 Y
5 N
6 Y
6 Y
6 Y
6 N
I should be adding a new column count in the same select which counts the number of 'Y' records for the ID and assigns it to all. (Eg: ID=5 has 3 records. All of them should be assigned the count value as '2').
Output required in select query:
ID Flag count
5 Y 2
5 Y 2
5 N 2
6 Y 3
6 Y 3
6 Y 3
6 N 3
Use a window function:
select id,
flag,
count(case when flag = 'Y' then 1 end) over (partition by id) as "count"
from the_table
order by id;
The case expression will return null for flags with N and thus they will be ignored by the count() function
I'm using Oracle SQL and i need help with a query. Hope it's not too much easy one. I did't find an answer for it in Google.
I have a table that need to be aggregated by ID column and then to select only the records that two values are included in a certain table (and both of them).
Table for example
ID | Value
1 | Y
1 | N
2 | N
2 | N
2 | Y
3 | Y
3 | Y
4 | Y
5 | Y
5 | N
5 | Y
5 | N
The output table need to include only the IDs that both Y and N are included in Value table. Output:
ID
1
2
5
Another solution that groups by the ID and uses HAVING to return only those with > 1 DISTINCT values:
with v_data(id, value) as (
select 1, 'Y' from dual union all
select 1, 'N' from dual union all
select 2, 'Y' from dual)
select id
from v_data
group by id
having count(distinct value) > 1
select distinct a.id
from your_table a inner join your_table b on a.id = b.id and a.value != b.value;
I have following 2 recordsets :
Recordset 1:
Id isVal isVal1
1 Y N
2 Y N
Recordset 2:
Id isVal isVal1
2 N Y
3 N Y
Actual recordset required is:
Id isVal isVal1
1 Y N
2 Y Y
3 N Y
Should I use join? Can you please advice me how can I solve this?
No, you want to place the records on top of each other so you would need to use union.
select id, max(isval) as isval, max(isval1) as isval1
from ( select id, isval, isval1
from recordset1
union all
select id, isval, isval1
from recordset1
)
group by id
I use union all as you don't need to remove duplicates, for which you would remove the all.
The max works because 'Y' is "greater" than 'N'.
I'm assuming that 'Y' takes precedence over 'N' rather than values from the first record-set are less important than values from the second.
I had the following query:
SELECT nvl(sum(adjust1),0)
FROM (
SELECT
ManyOperationsOnFieldX adjust1,
a, b, c, d, e
FROM (
SELECT
a, b, c, d, e,
SubStr(balance, INSTR(balance, '[&&2~', 1, 1)) X
FROM
table
WHERE
a >= To_Date('&&1','YYYYMMDD')
AND a < To_Date('&&1','YYYYMMDD')+1
)
)
WHERE
b LIKE ...
AND e IS NULL
AND adjust1>0
AND (b NOT IN ('...','...','...'))
OR (b = '... AND c <> NULL)
I tried to change it to this:
SELECT nvl(sum(adjust1),0)
FROM (
SELECT
ManyOperationsOnFieldX adjust1
FROM (
SELECT
SubStr(balance, INSTR(balance, '[&&2~', 1, 1)) X
FROM
table
WHERE
a >= To_Date('&&1','YYYYMMDD')
AND a < To_Date('&&1','YYYYMMDD')+1
AND b LIKE '..'
AND e IS NULL
AND (b NOT IN ('..','..','..'))
OR (b='..' AND c <> NULL)
)
)
WHERE
adjust1>0
Mi intention was to have all the filtering in the innermost query, and only give to the outer ones the field X which is the one I have to operate a lot. However, the firts (original) query takes a couple of seconds to execute, while the second one won't even finish. I waited for almost 20 minutes and still I wouldn't get the answer.
Is there an obvious reason for this to happen that I might be overlooking?
These are the plans for each of them:
SELECT STATEMENT optimizer=all_rows (cost = 973 Card = 1 bytes = 288)
SORT (aggregate)
PARTITION RANGE (single) (cost=973 Card = 3 bytes = 864)
TABLE ACCESS (full) OF "table" #3 TABLE Optimizer = analyzed(cost=973 Card = 3 bytes=564)
SELECT STATEMENT optimizer=all_rows (cost = 750.354 Card = 1 bytes = 288)
SORT (aggregate)
PARTITION RANGE (ALL) (cost=759.354 Cart = 64.339 bytes = 18.529.632)
TABLE ACCESS (full) OF "table" #3 TABLE Optimizer = analyzed(cost=750.354 Card = 64.339 bytes=18.529.632)
Your two queries are not identical.
the logical operator AND is evaluated before the operator OR:
SQL> WITH data AS
2 (SELECT rownum id
3 FROM dual
4 CONNECT BY level <= 10)
5 SELECT *
6 FROM data
7 WHERE id = 2
8 AND id = 3
9 OR id = 5;
ID
----------
5
So your first query means: Give me the big SUM over this partition when the data is this way.
Your second query means: give me the big SUM over (this partition when the data is this way) or (when the data is this other way [no partition elimination hence big full scan])
Be careful when mixing the logical operators AND and OR. My advice would be to use brackets so as to avoid any confusion.
It is all about your OR... Try this:
SELECT nvl(sum(adjust1),0)
FROM (
SELECT
ManyOperationsOnFieldX adjust1
FROM (
SELECT
SubStr(balance, INSTR(balance, '[&&2~', 1, 1)) X
FROM
table
WHERE
a >= To_Date('&&1','YYYYMMDD')
AND a < To_Date('&&1','YYYYMMDD')+1
AND (
b LIKE '..'
AND e IS NULL
AND (b NOT IN ('..','..','..'))
OR (b='..' AND c <> NULL)
)
)
)
WHERE
adjust1>0
Because you have the OR inline with the rest of your AND statements with no parenthesis, the 2nd version isn't limiting the data checked to just the rows that fall in the date filter. For more info, see the documentation of Condition Precedence