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Indefinitely. It's not the kind of cursor that a database gives out, which is a resource. A cursor in this context is just a pointer to some position in a set of results, something like "all results where date created is greater than $X". For SQL implementations, check out:

https://github.com/hasura/graphql-engine/issues/141#issuecom...

or

https://stackoverflow.com/questions/38017054/mysql-cursor-ba...

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It depends on the implementation. For example, the post mentions using Elasticsearch in production "which naturally supports this cursor stuff" but it has a max keep alive context duration of 24 hours[1] by default. This limit can be extended on a cluster level but it's unlikely they have it set to indefinite. Which means that their search context is likely only valid for 24 hours.

[1] https://www.elastic.co/guide/en/elasticsearch/reference/curr...

Yep, that’s the case if you use the scroll parameter, but their search_after API is not stateful and that’s the sort of thing this article is about.

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