Serializability

A combined outcome equivalent to some serial execution of the underlying updates

MARKO ŽIVKOVIĆ In review

Serializability (distributed systems and database theory) means the observed outcome of concurrent operations could have been produced by some serial (one-at-a-time) execution of those operations — no impossible interleaving of reads and writes.

A serializable snapshot or repeatable-read transaction at cut-off time T presents a state that existed at a point in a valid history. That typically yields U-low to U-med cross-stream consistency when T and the alignment method are disclosed — suitable for account views, reporting, and audit.

Serializability vs linearizability

	Serializability	Linearizability
Real-time order	Not required	Required — completed-before-start order preserved
Typical use	Snapshot reports, as-of analytics	Hard invariants, trading, robotics
Typical cross-stream uncertainty	U-low – U-med	U-low

Per-stream “current” values with no shared cut may fail serializability. Treating a best-effort dashboard as serializable without disclosure is impossible simultaneity on the read path.

Corpus stance

A2 — working context: Standard CS guarantee mapped to the epistemic uncertainty contract; not a substitute for causal consistency across independent writers without infrastructure support.