I have in my columns (ID) values
5
6
9
I want to select first missing IDfrom above 0. My desire select value will be 1.(if 1 exists then it will selects 2 and so on...).
I'm using this code:
SELECT MIN(id) As MinMissingId FROM table1 where id>=0
But my result is first existing ID and not missing
This will return the next unused id starting with 1, works in all cases, e.g. table is empty or there's no gap:
WITH cte AS
(
SELECT id FROM tab
UNION ALL
SELECT 0
)
SELECT MIN(id) + 1
FROM cte
WHERE NOT EXISTS
(
SELECT *
FROM tab
WHERE tab.id = cte.id + 1
)
You can do this by building on the answer in your related question.
select (case when min(id) > 0 then 1 else min(id) + 1 end)
from table1 t
where not exists (select 1
from table1 t2
where t2.id = t.id + 1
);
The idea is to find the first id that is missing. If it is bigger
Related
I'm currently having trouble writing the business logic to get rows from a table with id's and a flag which I have appended to it.
For example,
id: id seq num: flag: Date:
A 1 N ..
A 2 N ..
A 3 N
A 4 Y
B 1 N
B 2 Y
B 3 N
C 1 N
C 2 N
The end result I'm trying to achieve is that:
For each unique ID I just want to retrieve one row with the condition for that row being that
If the flag was a "Y" then return that row.
Else return the last "N" row.
Another thing to note is that the 'Y' flag is not always necessarily the last
I've been trying to get a case condition using a partition like
OVER (PARTITION BY A."ID" ORDER BY A."Seq num") but so far no luck.
-- EDIT:
From the table, the sample result would be:
id: id seq num: flag: date:
A 4 Y ..
B 2 Y ..
C 2 N ..
Using a window clause is the right idea. You should partition the results by the ID (as you've done), and order them so the Y flag rows come first, then all the N flag rows in descending date order, and pick the first for each id:
SELECT id, id_seq_num, flag, date
FROM (SELECT id, id_seq_num, flag, date,
ROW_NUMBER() OVER (PARTITION BY id
ORDER BY CASE flag WHEN 'Y' THEN 0
ELSE 1
END ASC,
date ASC) AS rk
FROM mytable) t
WHERE rk = 1
My approach is to take a UNION of two queries. The first query simply selects all Yes records, assuming that Yes only appears once per ID group. The second query targets only those ID having no Yes anywhere. For those records, we use the row number to select the most recent No record.
WITH cte1 AS (
SELECT id
FROM yourTable
GROUP BY id
HAVING SUM(CASE WHEN flag = 'Y' THEN 1 ELSE 0 END) = 0
),
cte2 AS (
SELECT *,
ROW_NUMBER() OVER (PARTITION BY t1.id ORDER BY t1."id seq" DESC) rn
FROM yourTable t1
INNER JOIN cte1 t2
ON t1.id = t2.id
)
SELECT *
FROM yourTable
WHERE flag = 'Y'
UNION ALL
SELECT *
FROM cte2 t2
WHERE t2.rn = 1
Here's one way (with quite generic SQL):
select t1.*
from Table1 as t1
where t1.id_seq_num = COALESCE(
(select max(id_seq_num) from Table1 as T2 where t1.id = t2.id and t2.flag = 'Y') ,
(select max(id_seq_num) from Table1 as T3 where t1.id = t3.id and t3.flag = 'N') )
Available in a fiddle here: http://sqlfiddle.com/#!9/5f7f9/6
SELECT DISTINCT id, flag
FROM yourTable
Let's say we have this table with columns RowID and Call:
RowID Call DesiredOut
1 A 0
2 A 0
3 B
4 A 1
5 A 0
6 A 0
7 B
8 B
9 A 2
10 A 0
I want to SQL query the last column DesiredOut as follows:
Each time Call is 'A' go back until 'A' is found again and count the number of records which are in between two 'A' entries.
Example: RowID 4 has 'A' and the nearest predecessor is in RowID 2. Between RowID 2 and RowID 4 we have one Call 'B', so we count 1.
Is there an elegant and performant way to do this with ANSI SQL?
I would approach this by first finding the rowid of the previous "A" value. Then count the number of values in-between.
The following query implements this logic using correlated subqueries:
select t.*,
(case when t.call = 'A'
then (select count(*)
from table t3
where t3.id < t.id and t3.id > prevA
)
end) as InBetweenCount
from (select t.*,
(select max(rowid)
from table t2
where t2.call = 'A' and t2.rowid < t.rowid
) as prevA
from table t
) t;
If you know that rowid is sequential with no gaps, you can just use subtraction instead of a subquery for the calculation in the outer query.
You could use a query to find the previous Call = A row. Then, you could count the number of rows between that row and the current row:
select RowID
, `Call`
, (
select count(*)
from YourTable t2
where RowID < t1.RowID
and RowID > coalesce(
(
select RowID
from YourTable t3
where `Call` = 'A'
and RowID < t1.RowID
order by
RowID DESC
limit 1
),0)
)
from YourTable t1
Example at SQL Fiddle.
Here is another solution using window functions:
with flagged as (
select *,
case
when call = 'A' and lead(call) over (order by rowid) <> 'A' then 'end'
when call = 'A' and lag(call) over (order by rowid) <> 'A' then 'start'
end as change_flag
from calls
)
select t1.rowid,
t1.call,
case
when change_flag = 'start' then rowid - (select max(t2.rowid) from flagged t2 where t2.change_flag = 'end' and t2.rowid < t1.rowid) - 1
when call = 'A' then 0
end as desiredout
from flagged t1
order by rowid;
The CTE first marks the start and end of each "A"-Block and the final select then uses these markers to get the difference between the start of one block and the end of the previous one.
If the rowid is not gapless, you can easily add a gapless rownumber inside the CTE to calculate the difference.
I'm not sure about the performance though. I wouldn't be surprised if Gordon's answer is faster.
SQLFiddle example: http://sqlfiddle.com/#!15/e1840/1
Believe it or not, this will be pretty fast if the two columns are indexed.
select r1.RowID, r1.CallID, isnull( R1.RowID - R2.RowID - 1, 0 ) as DesiredOut
from RollCall R1
left join RollCall R2
on R2.RowID =(
select max( RowID )
from RollCall
where RowID < R1.RowID
and CallID = 'A')
and R1.CallID = 'A';
Here is the Fiddle.
You could do something like that:
SELECT a.rowid - b.rowid
FROM table as a,
(SELECT rowid FROM table where rowid < a.rowid order by rowid) as b
WHERE <something>
ORDER BY a.rowid
As I cannot say which DBMS you are using this is more kind of pseudo code which could work based on your system.
My goal is combining all rows in 2 tables. The simplest example I can think of is:
Table 1
Letter
A
B
Table 2
Number
0
1
Combined Table
Letter Number
A 0
B 0
A 1
B 1
I have come up with this SQL statement:
select * from
(
select * From (
select 'A' as 'Letter'
UNION
select 'B' as 'Letter'
) as Letter
) as Letter,
(
select * from (
select 0 as 'Number'
UNION
select 1 as 'Number'
) as Number
) as Number
This works but I don't like it.
defining the same alias multiple times
7 select statements? really....
Does anyone know a cleaner way of doing this? I am sure the answer is out there already but I had no idea how to search for it. Thanks all
Try this
select * from table1 join table2 on 1=1
This is the Cartesian product and if that's what you want to get,
you just have to specify some join condition which is always true.
And try this too.
SELECT * FROM
(
SELECT 'A' AS ch
UNION ALL
SELECT 'B'
)
T1
JOIN
(
SELECT 0 AS dg
UNION ALL
SELECT 1
) T2
ON 1 = 1
In SQL Server you can also do this (if you find it more concise/clear).
SELECT *
FROM
(
VALUES
('A'),
('B')
)
AS ch1(ch)
JOIN
(
SELECT *
FROM
(
VALUES
(0),
(1)
)
AS dg1(dg)
) TBL
ON 1 = 1
Easy enough with CROSS JOIN...
SELECT *
FROM Table1
CROSS JOIN Table2
Result:
Letter Number
------------------------- -----------
A 0
B 0
A 1
B 1
(4 row(s) affected)
I want to get All records that has duplicate values for SOME of the fields (i.e. Key columns).
My code:
CREATE TABLE #TEMP (ID int, Descp varchar(5), Extra varchar(6))
INSERT INTO #Temp
SELECT 1,'One','Extra1'
UNION ALL
SELECT 2,'Two','Extra2'
UNION ALL
SELECT 3,'Three','Extra3'
UNION ALL
SELECT 1,'One','Extra4'
SELECT ID, Descp, Extra FROM #TEMP
;WITH Temp_CTE AS
(SELECT *
, ROW_NUMBER() OVER (PARTITION BY ID, Descp ORDER BY (SELECT 0))
AS DuplicateRowNumber
FROM #TEMP
)
SELECT * FROM Temp_cte
DROP TABLE #TEMP
The last column tells me how many times each row has appeared based on ID and Descp values.
I want that row but I ALSO need another column* that indicates both rows for ID = 1 and Descp = 'One' has showed up more than once.
So an extra column* (i.e. MultipleOccurances (bool)) which has 1 for two rows with ID = 1 and Descp = 'One' and 0 for other rows as they are only showing up once.
How can I achieve that? (I want to avoid using Count(1)>1 or something if possible.
Edit:
Desired output:
ID Descp Extra DuplicateRowNumber IsMultiple
1 One Extra1 1 1
1 One Extra4 2 1
2 Two Extra2 1 0
3 Three Extra3 1 0
SQL Fiddle
You say "I want to avoid using Count" but it is probably the best way. It uses the partitioning you already have on the row_number
SELECT *,
ROW_NUMBER() OVER (PARTITION BY ID, Descp
ORDER BY (SELECT 0)) AS DuplicateRowNumber,
CASE
WHEN COUNT(*) OVER (PARTITION BY ID, Descp) > 1 THEN 1
ELSE 0
END AS IsMultiple
FROM #Temp
And the execution plan just shows a single sort
Well, I have this solution, but using a Count...
SELECT T1.*,
ROW_NUMBER() OVER (PARTITION BY T1.ID, T1.Descp ORDER BY (SELECT 0)) AS DuplicateRowNumber,
CASE WHEN T2.C = 1 THEN 0 ELSE 1 END MultipleOcurrences FROM #temp T1
INNER JOIN
(SELECT ID, Descp, COUNT(1) C FROM #TEMP GROUP BY ID, Descp) T2
ON T1.ID = T2.ID AND T1.Descp = T2.Descp
I have a table that looks as under
SALES_ORDER_ID DATEDIFFERENCE FLAG
1 -40 1
1 -20 1
2 40 0
2 -10 1
3 12 0
4 -70 1
5 60 0
5 23 0
//ddl
Declare #t table (sales_order_id int,DateDifference int, Flag int)
Insert Into #t
Select 1,-40,1 Union All Select 1,-20,1 Union All
Select 2,40,0 Union All Select 2,-10,1 Union All
Select 3,12,0 Union All Select 4,-70,1 Union All
Select 5,60,0 Union All Select 5,23,0
Select *
From #t
The output should be
sales_order_id DateDifference Flag
3 12 0
5 60 0
5 23 0
i.e. the group (Sales_Order_Id) where all the items are having the Flag as 0.
I mean Sales_Order_Id = 2 will not appear since at least one item is not zero (2,-10,1)
Please do ask me if the information is not sufficient.
How to do this query?
Edit
I found my answer.. though still looking for a more elegant one
;with cte as(
Select
sales_order_id = Case when x.sales_order_id is null then y.sales_order_id else x.sales_order_id end
,x.CountFor0
,y.CountFor1
From
(Select sales_order_id,CountFor0 = count(*)
from #t
where Flag = 0
group by sales_order_id )x
Full Join
(Select sales_order_id,CountFor1 =count(*)
from #t
where Flag = 1
group by sales_order_id )y
On x.sales_order_id = y.sales_order_id)
Select *
From cte
where CountFor1 is null
Thanks to all
Since I don't have much reputation , so cannot post my answer in answer section
Try this..
SELECT sales_order_id,DateDifference,Flag FROM #t WHERE sales_order_id NOT IN
(SELECT sales_order_id FROM #t WHERE Flag=1)
Good day!
I think that will help:
Select * from #t WHERE FLAG=0;
I just wanted to add that this is a great place to use windows functions:
select sales_order_id, DateDifference, flag
from (select t.*, SUM(flag) over (partition by sales_order_id) as sumflag
from #t t
) t
where sumflag = 0
Ok, now I understand what you are trying to do. You can use NOT EXISTS, as others have suggested (sqlfiddle):
SELECT *
FROM #t T1
WHERE Flag = 0
AND NOT EXISTS (
SELECT *
FROM #t T2
WHERE T1.sales_order_id = T2.sales_order_id
AND T2.Flag <> 0)
You can also use NOT IN, as others have also suggested (sqlfiddle):
SELECT *
FROM #t T1
WHERE Flag = 0
AND sales_order_id NOT IN (
SELECT sales_order_id
FROM #t T2
WHERE T2.Flag <> 0)
And you can even use a JOIN and check the joined table has no row (id is NULL) (sqlfiddle):
SELECT *
FROM #t T1
LEFT OUTER JOIN #t T2 ON T1.sales_order_id = T2.sales_order_id AND T2.Flag <> 0
WHERE T1.Flag = 0
AND T2.sales_order_id IS NULL
Original answer:
You need a WHERE clause to filter the results:
SELECT *
FROM #t
WHERE Flag = 0
Check out the sqlfiddle here
I am assuming you also want the (2,40,0) row in the results, though.
select *
from #T as T1
where not exists(select *
from #T as T2
where T1.sales_order_id = T2.sales_order_id and
T2.Flag = 1)
try this:
Select * From #t
where Flag=0 and sales_order_id not in
(select sales_order_id from #t where Flag !=0)