Why not create a partition table, in the table all the 'rules' you use to decide which partition a row should go, that could be any number of fields, then...

What I sometimes do, is run a query and time it.
Then rerun the query and time it.
Clear the cache, then rerun the query and time is.

And...

If there is only one product, I would make an auxilary table containing all possible/allowed number of these products and all packaging solutions. And have at least one row for...

Without model and/or data, it's a bit difficult to give a definite answer.

Example:

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-- Ben Brugman
-- 20180906
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drop table if exists testgr

Without model and/or data, it's a bit difficult to give a definite answer.

But I think that this can be solved with Grouping on the  ClaimsOfficer/Claimtype.
And for the...

I did play around with the suggested functions.

Thanks for all your replies, they were usefull to me.
Ben

Hello,
Does this help, use the Lead function to see if the next row is a start row, then declare the actual row the end row.
If there is not...

As with the others:
A bit of overprocessing.
Maybe you should look at triggers to maintain the seconde database.

Maybe or maybe not usefull :
Use a view...

The uniquifier

While reading the uniquifier does not do a lot for efficiency. It is not part of the selection mechanism, it is not part of the ordering mechanismn....