First rows in Table A- process and write it to table



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First rows in Table A- process and write it to table

Postby raulravi » Thu Dec 13, 2012 4:48 pm

Hi,
I have to read 5 first rows in Table A- process and write it to table B. And gain read next five rows (from 6-10 ) again process and write them to table B.

Can any one help me out here?
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Re: First rows in Table A- process and write it to table

 

Re: CICS-DB2

Postby Robert Sample » Thu Dec 13, 2012 5:06 pm

Since this is a HELP forum and not a WRITE-THE-CODE-FOR-YOU forum, what have you done so far and what is your problem?

And what does "first five rows" mean to you since DB2 does not guarantee you will get the rows in any particular order (unless you use ORDER BY in your SELECT)?
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Re: CICS-DB2

Postby dick scherrer » Thu Dec 13, 2012 8:38 pm

Hello and welcome to the forum,

I have to read 5 first rows in Table A- process and write it to table B. And gain read next five rows (from 6-10 ) again process and write them to table B.
Why does someone believe this should be done? What business requirement does it meet?

Hopefully, you are aware that in database there is no concept of first/last n rows. Even with an ORDER BY, the result can change due to inserts/deletes.
Hope this helps,
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Re: CICS-DB2

Postby GuyC » Mon Dec 17, 2012 3:52 pm

you could use multi-row fetch, multi-row insert.
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Re: First rows in Table A- process and write it to table

Postby dick scherrer » Mon Dec 17, 2012 8:10 pm

Hi Guy,

Yup, surely could - but i'm still curious Why . . . ?

d
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Re: First rows in Table A- process and write it to table

Postby GuyC » Tue Dec 18, 2012 2:59 pm

80% of programs read/fetch from some input (table) , process, and write/insert some output (table).
That's almost the definition of "a program".
Why it should be in batches of 5 I have no idea. maybe he needs to print them side by side, package 5 items in a box, commit every 5, ...
He could just fetch 5 times, but multi-row is faster
I can explain it to you, but i can not understand it for you.
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Re: First rows in Table A- process and write it to table

Postby Akatsukami » Tue Dec 18, 2012 4:45 pm

I think that the intent of the question may have been, "But how does this help in ensuring that the first five rows are gotten, and then the next five rows?".
"You have sat too long for any good you have been doing lately ... Depart, I say; and let us have done with you. In the name of God, go!" -- what I say to a junior programmer at least once a day
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