Aggregate provenance

Functions for building and evaluating aggregate (GROUP BY) provenance, including the δ-semiring operator and semimodule multiplication. More...

Functions
UUID	provsql.provenance_delta (UUID token)
	Create a δ-semiring gate wrapping a provenance token.
AGG_TOKEN	provsql.provenance_aggregate (INTEGER aggfnoid, INTEGER aggtype, ANYELEMENT val, UUID[] tokens)
	Build an aggregate provenance gate from grouped tokens.
UUID	provsql.provenance_semimod (ANYELEMENT val, UUID token)
	Create a semimodule scalar multiplication gate.

Detailed Description

Functions for building and evaluating aggregate (GROUP BY) provenance, including the δ-semiring operator and semimodule multiplication.

Function Documentation

provenance_aggregate()

AGG_TOKEN provsql.provenance_aggregate	(	INTEGER	aggfnoid,
		INTEGER	aggtype,
		ANYELEMENT	val,
		UUID[]	tokens
	)

Build an aggregate provenance gate from grouped tokens.

Called internally by the query rewriter for GROUP BY queries. Creates an agg gate linking all contributing tokens and records the aggregate function OID and the computed scalar value.

Parameters

aggfnoid	OID of the SQL aggregate function
aggtype	OID of the aggregate result type
val	computed aggregate value
tokens	array of provenance tokens being aggregated

Source code

provsql.sql line 1167

provenance_delta()

UUID provsql.provenance_delta

(

UUID

token

)

Create a δ-semiring gate wrapping a provenance token.

Used internally for aggregate provenance. Returns the token unchanged if it is gate_zero() or gate_one(), and gate_one() if the token is NULL.

provenance_semimod()

UUID provsql.provenance_semimod	(	ANYELEMENT	val,
		UUID	token
	)

Create a semimodule scalar multiplication gate.

Pairs a scalar value with a provenance token, used internally by the query rewriter for aggregate provenance.

Parameters

val	the scalar value
token	the provenance token to multiply

Source code

provsql.sql line 1207