Combining two seperate tables into one

Hello!
I don`t know how to do some query. I have two tables which looks like
it:
First table:
MRPC 200504 200505 200506
C01 1 2 3
C02 2 3 4
C03 3 3 2
Second table:
MRPC 200504 200505 2000506
C01 20% 20% 50%
C02 10% 30% 70%
C03 30% 40% 15%
I would like to combine these two tables into one table, which would
look like it:
MRPC 200504 200504 PRC 200505 200505 PRC 200506 200506 PRC
C01 1 20% 2 20% 3 50%
C02 2 10% 3 30% 4 70%
C03 3 30% 3 40% 2 15%
The number of columns is changeable, because once a w there is extra
column added. Is it possible to link these two tables and create one
score table? As you can see the second table has the same columns as
first one and don`t have a string "PRC" in the name of column.
Thank you for your help
Marcin from Poland
*** Sent via Developersdex http://www.examnotes.net ***>> Is it possible to link these two tables and create one score table?
Yes it is possible, but unless you are working towards achieving some
performance benefits (for instance, by materializing data) for specific
queries, such an attempt is of little use. You can always derive the
resultset using a simple JOIN -- in many cases a view should be the
solution.
Keeping them separate, on the other hand, allows you to manipulate data in
each table separately without affecting the other.
It is not a show-stopper, just the matter of aliasing the column names.
Anith|||On Fri, 05 Aug 2005 09:05:05 -0700, Marcin Zmyslowski wrote:

>
>Hello!
>I don`t know how to do some query. I have two tables which looks like
>it:
>First table:
>MRPC 200504 200505 200506
>C01 1 2 3
>C02 2 3 4
>C03 3 3 2
>Second table:
>MRPC 200504 200505 2000506
>C01 20% 20% 50%
>C02 10% 30% 70%
>C03 30% 40% 15%
>I would like to combine these two tables into one table, which would
>look like it:
>MRPC 200504 200504 PRC 200505 200505 PRC 200506 200506 PRC
>C01 1 20% 2 20% 3 50%
>C02 2 10% 3 30% 4 70%
>C03 3 30% 3 40% 2 15%
>
>The number of columns is changeable, because once a w there is extra
>column added. Is it possible to link these two tables and create one
>score table? As you can see the second table has the same columns as
>first one and don`t have a string "PRC" in the name of column.
Hi Marcin,
Instead of adding columns to your tables for each w, why not add one
column to the table to hold the w, then just add rows?
The first table would look like this:
MRPC W Data
C01 200504 1
C01 200505 2
C01 200506 3
C02 200504 2
C02 200505 3
C02 200506 4
C03 200504 3
C03 200505 3
C03 200506 2
The second table would be similar. Depending on actual business
requirements, it might also be possible to combine these two tables:
MRPC W Data PRC
C01 200504 1 20%
C01 200505 2 20%
C01 200506 3 50%
C02 200504 2 10%
C02 200505 3 30%
C02 200506 4 70%
C03 200504 3 30%
C03 200505 3 40%
C03 200506 2 15%
(BTW, what datatype do you use for the percentages?)
Tables with a seperate column for each w/month/year/whatever tend to
bring lots of probles and no gain.
Best, Hugo
--
(Remove _NO_ and _SPAM_ to get my e-mail address)|||Hi!
I could have data in rows, but I can only do a crosstab query which let
me create one columns (wk), not two columns at the same time: "wk" and
"wk prc", that`s, why I really need data (WK and WK prc) in columns. I
still don`t know how to combine these two tables into one. Could you
give me a code example' I cannot find it in archieve. I would be very
grateful for help.
Thanx, Marcin from Poland
*** Sent via Developersdex http://www.examnotes.net ***|||On Mon, 08 Aug 2005 00:54:37 -0700, Marcin Zmyslowski wrote:

>Hi!
>I could have data in rows, but I can only do a crosstab query which let
>me create one columns (wk), not two columns at the same time: "wk" and
>"wk prc", that`s, why I really need data (WK and WK prc) in columns. I
>still don`t know how to combine these two tables into one. Could you
>give me a code example' I cannot find it in archieve. I would be very
>grateful for help.
>Thanx, Marcin from Poland
Hi Marcin,
Doing a cross tab is actually better handled by the presentation tier.
But if there is no way that the client can handle this and you must do
it server side, use something like this untested code:
SELECT MRPC,
MAX(CASE WHEN W = '200504' THEN Data END) AS '200504',
MAX(CASE WHEN W = '200504' THEN PRC END) AS '200504 PRC',
MAX(CASE WHEN W = '200505' THEN Data END) AS '200505',
MAX(CASE WHEN W = '200505' THEN PRC END) AS '200505 PRC'
FROM YourTable
GROUP BY MRPC
Best, Hugo
--
(Remove _NO_ and _SPAM_ to get my e-mail address)sqlsql