dynamic operations with 2 tables and 1 insert SQL Server
I have 2 tables:
table1
id someval someatt
-------------------
1 23 name1
2 56 name2
3 76 name3
4 456 name4
5 53 name5
6 67 name6
7 12 name7
8 43 name8
9 99 name9
10 567 name10
table2
id someval someatt
-------------------
1 23.3 name1
2 5.6 name2
3 8.76 name3
4 4.56 name4
5 5.3 name5
6 6.7 name6
7 1.2 name7
8 开发者_开发问答 4.3 name8
9 9.9 name9
10 56.7 name10
I need to insert to a new table some operations of various fields of both tables so, for example
iteration1
x = get value from table1 where id 1
y = get value from table1 where id 2
a = get value from table2 where id 1
b = get value from table2 where id 2
iteration2
r = get value from table1 where id 2
s = get value from table1 where id 3
u = get value from table2 where id 2
v = get value from table2 where id 3
iterationn.
q = get value from table1 where id n-1
p = get value from table1 where id n
o = get value from table2 where id n-1
e = get value from table2 where id n
Then insert into NEWTABLE
(a*b + x+y), (r*s + u*v) ...(q*p+o*e)
sO I was thinking (IF I have to do this 100 times):
SET @counter = 1;
SET @template = '';
SET @N = 100;
WHILE(@counter < @N)
Select @x = value from table 1 where id = @counter
Select @y = value from table 1 where id = @counter + 1
Select @a = value from table 2 where id = @counter
Select @b = value from table 2 where id = @counter + 1
@template = @template + ' (@x*@y + @a*@b), '
end
so at the end of the loop I have a full template
and then EXEC(@template)
,
- How could you optimize this?
- How to do something like I described? (table1 and table2 are samll examples of my tables)
- Is there a way The 4 select statements are avoided?
output table:
result1 result2 result3 .... result100
---------------------------------------
float float float ... float
where float is a result of calculating (a*b + x+y)
for each value in table1 and table2
This will work with SQL 2005 & up, using the same data you listed.
SELECT t1x.id AS smaller_id,
( t1x.someval * t1y.someval ) + ( t2a.someval * t2b.someval ) AS result
FROM dbo.table1 AS t1x
INNER JOIN dbo.table1 AS t1y ON t1x.id + 1 = t1y.id
INNER JOIN dbo.table2 AS t2a ON t2a.id = t1x.id
INNER JOIN dbo.table2 AS t2b ON t2b.id = t1y.id
If you want it horizontal, you'll have to PIVOT the results.
SELECT 'Calculation Result' AS CalcRes,
[result1], [result2], [result3], [result4], [result5], [result6], [result7], [result8], [result9]
FROM (
SELECT 'result' + cast(t1x.id AS varchar(4)) AS result_name,
( t1x.someval * t1y.someval ) + ( t2a.someval * t2b.someval ) AS result
FROM dbo.table1 AS t1x
INNER JOIN dbo.table1 AS t1y ON t1x.id + 1 = t1y.id
INNER JOIN dbo.table2 AS t2a ON t2a.id = t1x.id
INNER JOIN dbo.table2 AS t2b ON t2b.id = t1y.id
) AS Results
PIVOT (
min( result ) --there needs to be an aggregate function here
FOR result_name IN ([result1], [result2], [result3], [result4], [result5], [result6], [result7], [result8], [result9])
) AS PivotedResults
You'll need to use dynamic SQL for this, because you need to know the names of your result colums before you pivot.
Join all the records together:
insert
NEWTABLE (theid, newval)
select
t1_p.id as theid
(t2_p.someval * t2_n.someval) + (t1_p.someval * t1_n.someval) as newval
from
Table1 t1_p
inner join
Table1 t1_n on t1_p.id + 1 = t1_n.id
inner join
Table2 t2_p on t1_p.id = t2_p.id
inner join
Table2 t2_n on t1_n.id = t2_n.id
Not sure I understand your question fully but....
;with cte1 as
(
select
T1_1.id,
T1_1.someval as x,
T1_2.someval as y
from @T1 as T1_1
inner join @T1 as T1_2
on T1_1.id = T1_2.id-1
),
cte2 as
(
select
T2_1.id,
T2_1.someval as a,
T2_2.someval as b
from @T2 as T2_1
inner join @T2 as T2_2
on T2_1.id = T2_2.id-1
)
select (a*b + x*y)
from cte1 as T1
inner join cte2 as T2
on T1.id = T2.id
Might you try something like
INSERT INTO SomeTable
SELECT
(x.value * y.value) + (a.value * b.value)
FROM
Table1 x
Table1 y on y.id = x.id + 1
Table2 a on a.id = x.id
Table2 b on b.id = x.id + 1
WHERE
x.Id = @counter
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