On 2017-11-07 08:27, hmidi slim wrote:
> Hi,
> Thank for your proposition but when to use this query :
> (to_tsvector('english', document) || to_tsvector('french', document)) @@
> (to_tsquery('english', query) || to_tsquery('french', query))
> I think that the performance decrease and not a good solution for big
> amount of data. Is it?
You have more lexems when you combine two languages, but not twice as
many as there will be some overlap. That means your index will also be
be bigger than a single language index. Anyhow I would expect this
variant to perform better than querying two single columns
simultaneously. Maybe one of the FTS developers could comment on this?