I don't understand your data manipulation requirements. It would be better if you edit your post to put your code in between <code>...</code> tags.

I think you could save a lot of work by pushing the data manipulation into the database instead of running a loop in Perl to do the data manipulation. If you need the count of FIELD1 that are equal, that's just some basic SQL:

select field1, count(*)
from mytable
group by field1

[download]

Your other query seems to have some more convoluted logic, but if you can reformulate it in a more descriptive than prescriptive way, it will be translatable to SQL far more easy. You use vocabulary like "loop until find a valid entry", which I guess means "not equal to '-'". My guess at it is the following, but I'm unclear on whether you want to actually manipulate the data or just return a result:

select field1
from mytable l
where field2 <> '-'
order by field1, field2

[download]

or, if you only want all the "first" rows of field1 where field2 is not '-', then maybe the following returns what you need:

select field1, min(field2)
from mytable l
where field2 <> '-'
group by field1
order by field1, field2

[download]

In reply to Re: DBI efficient loop? by Corion
in thread DBI efficient loop? by lorenzov

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