So I finally started to use the "context" feature. I've been using a JSON-DB successfully for years. I used global.set(query, data) where data is JSON. This works. But when the "query" has a "." inside, the key is broken up in the resulting JSON database (the filesystem global/global.json) will br…

[image] bakman2: I have objects with more than 1 million elements sitting in flow/global context, Are those in persistent storage using the file context? If so I would be a bit worried about writing that out every 30 seconds. I think it writes the whole flow or global context whenever anythi…

[image] bakman2: Storing as an object can help with performance, especially when retrieving a value as you only need the key eliminating the need to traverse an array. That's a good point. If there are many records then an object is clearly better. And where the unique key is an email addres…

My largest file-based store is around 200,000 and it has no problems with that though it doesn't really update any more. I have one around 75,000 that updates (extends) weekly, again no issues. But yes, I wouldn't want to do this with something that is updated very rapidly. Especially as my write p…

[image] jbudd: And where the unique key is an email address I would probably use a "sanitised" string as the key (as suggested by Julian above) Just note that I don't believe that the deep key approach is any more (or less) efficient than getting/setting the whole object since it has to be re…

[image] Colin: tes the whole flow or global context whenever anything changes, at the next 30 second boundary (configu Thanks for discussion. It seems the issue is writing out to disk and how much is written? If I get a large array, and modify it - I would think the entire array is written t…

[image] knowledgeshark: I would think the entire array is written to disk. In the simplest case of filesystem context store then yes, but it could also depend on other operating system factors - eg using an overlay file system, (such as in docker), can mean that only changes are written to di…

Without that docker overlay issue, just to clarify: This saves to the filesystem (assuming on), index by "value1". global.get("value1"); global.set("value1",<stuff>); Then I add another value. (Assuming value1 already saved) global.get("value2"); global.set("value2",<stuff>); Will only the "val…

[image] knowledgeshark: Will only the "value2" get written to disk? Actually, this is worse than I'd realised. If you are using the file store, ALL GLOBALs seem to be written to a single file! ~/.node-red/context/global/global.json [image] [image] This is not at all how I thought it woul…

the flow/global variables are evaluated as javascript objects if i am not mistaken, not as JSON, thus they will break on the dot notation. Use a simple approach: const obj = { users: [ { email: "some.email@gmail.com", category: "uncle", "uuid":123 } ] } global.set("somevar", obj) to return r…

That javascript object notation is a strange constraint for a key. I assume there are implementation simplicities, but we don't access that object by name outside of the "global.get" as far as I know, so why not keep it as JSON doesn't mind. As the storage is JSON, I think it should mirror what the…

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Saving in global context parses key, breaking on "." shown in JSON

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christopher-lambe 23 April 2026 14:14 36

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Saving in global context parses key, breaking on "." shown in JSON

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