Performance: concepts with rich hierarchy

[Alexdavv]

The pages of concepts with rich hierarchy are extremely heavy (>10MB) and basically unresponsive:

http://athena.ohdsi.org/search-terms/terms/35626993

How we actually want to represent such long lists?

[gklebanov]

in cases like this, we should really be implementing "lazy load", e.g loading things in chunks (50 terms, for example) as people are scrolling through the list

@olga-ganina - please add to the backlog

[cgreich]

We wanted a lazy load anyway, where the hierarchy is not pre-loaded, and gets only pulled when the user clicks on "Hierarchy". And yes, for the 10MByters we can introduce chunkwise download, with "More" on the bottom.

[acumarav]

Hierarchy lazy loading already implemented within OHDSI/Athena#96, but here is a different problem: Concept relationships count is really huge: 104246 and it should be rendered on a single page. Not every browser can render such a huge table and it will hardly be usable after.

I am not sure about lazy loading because the page will become irresponsive later. I think we need something like - not to render more than e.g. 5K rows. but offer a link to download the CSV file for the local explorations. We can show a message saying something like: "Concept contains too many (NUMBER) rows that cannot be rendered. Please download CSV if you want to explore whole list locally. @gklebanov @cgreich - what do you think about offline download or paging + download?

[Alexdavv]

For some of the popular concepts the page cannot be loaded at all: https://athena.ohdsi.org/search-terms/terms/40642538

[thisismexp]

I just stumbled upon this issue as I wanted to make a feature request for pagination functionality for concepts with a high number of relationships. A usable solution (in my eyes) would be to keep displaying all distinct relationship types (relationship_id) but for each type only show a number (e.g. 10) of relationships, and providing pagination if there are more.