io.SinkChange

What a sink writes for one state of its node: the change since the

Usage

io.SinkChange(
    view,
    contract,
    schema,
    change,
)

state it wrote last, or the whole table.

The tables are built when first used, so a sink that reads only inserts and deletes does not build table.

Attributes

contract: What to record with the write (Contract): the node, the plan, the source versions and what the node proved about every row. contract.epoch grows with every state; a sink that stores it can tell the state it holds (Sink.contract).
schema: The table’s schema: the node’s columns, NOT NULL where the node proves it.
replace: True if the sink’s contents must be replaced by table: the first write, contents this process did not write, or contents another plan wrote. Then inserts is table and deletes is empty.

Attributes

Name	Description
change	The weighted change from the state written last to this one
deletes	The rows to remove, one copy each (with replace, none).
inserts	The rows to add (with replace, every row).
native	The state and the change as tables DuckDB holds, when the view
table	The node’s whole state.

change

The weighted change from the state written last to this one

change: pa.Table

(sverify._weighted): the copies each row gains or loses, as the view’s changes since then add up.

deletes

The rows to remove, one copy each (with replace, none).

deletes: pa.Table

inserts

The rows to add (with replace, every row).

inserts: pa.Table

native

The state and the change as tables DuckDB holds, when the view

native: tuple[Resident, Resident] | None

keeps its state in DuckDB (sverify._state.DuckDBStore): the new state’s rows (a DuckDB view), and the weighted change since the state written last (with replace, the whole state), computed by the view’s merge plan in DuckDB. None otherwise: write the Arrow tables.

table

The node’s whole state.

table: pa.Table