How does it support Mutable Data?

BNB Greenfield
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Alternative solutions like IPFS/Filecoin Arweave only support immutable data and are mainly suitable for static & immutable data.

Is it also true for greenfield? Does it support data mutability?

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Ans:
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Hey Liang,

thanks for the questions, let us reply in the forum directly.

But shortly, greenfield support the deletion of a file, which means that by default a file can be deleted by a user if the user as the right ownership.

In principale If nobody has the access right to delete a file this file would be alive as long as the payment flow to keep the file is active.
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Qns:
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Thanks for the reply

  1. so what is the identifier of a file (how is the ID derived?)
  2. if users can delete a file, does that mean they could “update” a file as well?

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  1. All objects can be identified and accessed via a universal path:

gnfd://<bucket_name>/[prefix]/[0…n]/object-id

where:

  • “gnfd://” is the fixed leading identifier, which is mandatory
  • bucket_name is the bucket name of the object, which is mandatory
  • prefix and other prefixes are all prefixes defined for the object, which are optional
  • object-id is the ID for the object, which is mandatory

This path should be 1:1 mapped to an object.

  1. Updating an existing object doesn’t differ from creating it in the first place, i.e. the very same operation is used to upload the object and will overwrite the existing one.

It will however be deleting and uploading a new one - not updating. So if you need to update a 1Mb file with 1 byte, you’ll have to upload the whole file again.

Updating usually suggests adding bytes to the existing file, without uploading/rewriting the whole file - this is not possible.

1 Like
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Is data read/write performance tied to block time or independent?
Say if I want to store database blobs on GreenField, since there is only “overwrite”, an I am encouraged to batch and write instead of doing small updates?

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independent. The data is uploaded directly to the storage provided. once uploaded, the checksum of the data along with other metadata, like permissions, are recorded to the blockchain - only this last part is tied to the block time