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Re: Creating index



fixed

Now I'm really confused!

And index tells how to sort the records - like the ORDER BY - more recently it IS possible to put a WHERE clause into it.

An index does not list the columns to return - that is done in a view.

A view is essentially a SELECT statement - without ORDER BY - that is contained in a file - actually an LF with SQL characteristics.

I'm not sure how a view creates an index - Alan, please explain more.

With a view, the SELECT statement is optimized at run-time, it is a dynamic SELECT - the optimizer will decide which indexes, if any, should be used to most efficiently run the view. It may end up creating a temporary index, but that is no different than any SQL processing now.

The point of index advice is to give a hint to which index might be helpful, so that it doesn't have to be created at run-time.

I hope that makes a little sense - you say in the other thread that this vendor says just to create some LFs or indexes - seems you're not getting much help.

I rather doubt even the need for this data warehouse - if the data is already somewhere, it can be read and used - and you may already have most of the indexes you need.

Especially when this DW ends up being this mostrosity that is giving you so much trouble.

Of course, as these things go, it's probably too late to pull the plug!!

Again - good luck!
Vern

On 12/26/2013 5:59 PM, Alan Campin wrote:
You don't. View will create index at runtime.
On Dec 26, 2013 3:49 PM, "Hoteltravelfundotcom" <hoteltravelfun@xxxxxxxxx>
wrote:

Hi Does one create an index via VIEW? I am not seeing how to do this.
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