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w3c / IndexedDB

Indexed Database API
https://w3c.github.io/IndexedDB/
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Clarify that IndexedDB's consistency model is strict serializability #355

Open taymonbeal opened 3 years ago

taymonbeal commented 3 years ago

This is implicit from the algorithms in the spec, but this is such a foundational question for any kind of distributed database (even distributed among tabs on a user's machine) that it'd probably be good to state explicitly in some non-normative text. (Maybe with a link to the Jepsen definition or something.)

inexorabletash commented 3 years ago

Despite being the editor on this spec, I wouldn't consider myself a database expert. So if anyone wants to suggest where to put a section like this, and what it should cover (e.g. ACID), please put comments here (or a PR...)

amirouche commented 2 years ago

Here is what I use so far:

(okdb-transaction-hygiene [symbol]) symbol? → symbol?

The parameter okdb-transaction-hygiene may be used to get or set transaction guarantees related to isolation, and consistency. The following symbols may be accepted:

  • read-uncommitted
  • read-committed
  • snapshot
  • serializable

ref: https://source.wiredtiger.com/10.0.0/transactions.html#transaction_isolation

Then a transaction is explained as follow:

(okdb-in-transaction okdb proc [failure [success]]) okdb? procedure? procedure? procedure? → any? ... ↑ okdb-conflict?

Rationales: [...]

okvs-in-transaction describes the extent of the atomic property, the A in ACID, of changes against the underlying database. A transaction will apply all database operations in PROC or none: all or nothing. When okdb-in-transaction returns successfully, the changes will be visible for future transactions, and implement durability, D in ACID. In case of error, changes will not be visible to future transactions in all cases. Regarding isolation, and consistency, respectively the I and C in ACID, it depends on the parameter okdb-transaction-hygiene.

Based and adjusted from https://git.sr.ht/~amirouche/okdb/