Group: General Forum Members
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Visits: 1267
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create table t1
(key int,
cnt int
)
insert into t1
select 2,5
union all
select 100,20
union all
select 4,8
union all
select 15,5
create table t2
(c1 int,
c2 int
)
insert into t2
select 1001,2
union all
select 82,100
union all
select 83,100
union all
select 84,100
union all
select 101,4
union all
select 102,4
union all
select 2000,15
union all
select 2001,15
Expected output should be as below:
First off, please execuse me if there is any issue with my language.
I have two tables, "t1" and "t2".
Based on the "cnt" column from t1 table, "key" value from t1 table we should repeat the Key value from t1 in table t2 based on the count "cnt" column. Basically, the "key" value has to be repeated "cnt" number of times and should be inserted into t2.
Also, we need to take the "c1" column into account, while repeating the rows. if we need to check the rows in t2 and if the "key" is not getting repeated "cnt" number of times in table t2, then we need to generate the extra rows to match the count.
for newly generated rows, we need make use of c1 column values repeatedly starting from 1st value for that particular "key" value/
For now, i am not looking of insertion, but I am looking for a select statement which returns rows as follows. Can anybody help?
c1 c2
1001,2
1001,2
1001,2
1001,2
1001,2
82,100
83,100
84,100
82,100
83,100
84,100
82,100
83,100
84,100
82,100
83,100
84,100
82,100
83,100
84,100
82,100
83,100
84,100
82,100
83,100
101,4
102,4
101,4
102,4
101,4
102,4
101,4
102,4
2000,15
2001,15
2000,15
2001,15
2000,15
Thanks,
Sam
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Group: General Forum Members
Points: 165572
Visits: 21618
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-- Works for cnt <= 10
-- Expand the inline tally for cnt > 10
;WITH Process AS (
SELECT t2.*, t1.cnt,
rn = ROW_NUMBER() OVER(PARTITION BY c2 ORDER BY c1)
FROM (SELECT c1, c2, GroupSize = COUNT(*) OVER(PARTITION BY c2) FROM #t2) t2
LEFT JOIN #t1 t1
ON t1.[key] = t2.c2
CROSS APPLY (
SELECT TOP(CAST(ROUND(t1.cnt/(GroupSize*1.0), 0) AS INT)) n
FROM (VALUES (0),(0),(0),(0),(0),(0),(0),(0),(0),(0)) d (n)
) x
)
SELECT c1, c2
FROM Process
WHERE cnt >= rn
ORDER BY c1
“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw
For fast, accurate and documented assistance in answering your questions, please read this article. Understanding and using APPLY, (I) and (II) Paul White Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff ModenExploring Recursive CTEs by Example Dwain Camps
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