Fabrice,

sorry for letting you wait.

Yes, it might help to increase the value for MAXCATS. All resulting statistics will be stored in the database, even if the text and/or attribute indexes are turned off. As you already indicated, it may happen that memory gets low.

If your data is rather static, one common alternative is to manually extract and generate index data in additional databases. In your particular case, this could look as follows:

1. Create "index" database

2. Perform queries to fill index database, e.g.:

let $name := "myidentifier" let $data := document { distinct-values ( db:open("db")//descendant::*[name() = $name] ) } db:add("index", $data, $name)

3. Perform queries, based on both databases

let $db := db:open("db") let $index := db:open("index", "myidentifier") for $i in $index/* return ...

Reg. the memory constraints: you may also split up your data in several databases and access all of them in a single query:

for $i in 1 to 100 let $db := db:open("db" || $i) return ...

Hope this helps, Christian ___________________________

I 'm working on a big database (more than 100 Go) containing several millions of articles, identified by a unique element.

I frequently iterate on the identifiers list, each time I have to compute distinct-values(//myidentifier) in order to build that list.

Could it help to set MAXCATS to 2 000 000 or 3 000 000 before creating the database ?

I cannot try it, because text index generation throws a heap overflow.

Could it be possible to improve the MAXCATS option in order to set a individual MAXCATS value for a specified element or attribute ?

Finally, is there a way to complete the text index generation (Xmx is already set to maximum) ?

Best regards,

Fabrice ETANCHAUD Senior Software Engineer

edital

Berkenlaan 1

B-1831 Brussels, Belgium

+32 2 716 32 32 general

+32 2 716 32 20 fax

fetanchaud@edital.com

corsearch.com | edital.com

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