pub const SCAN_KEY: &str = "__oqx_scan";Expand description
The key of a lazy ROOT SCAN marker: { "__oqx_scan": "docs" } stands for
^docs / a bare docs at the root until the engine reads it in row position
(to_rows) or is about to observe it as a value (materialize — an
operand, an argument, a projected item, a key), or probes it through
index_for, in which case the scan never runs. The marker never reaches
the language: the engine materializes every value it observes, so ==,
in, entries(…), size(…), truthiness, distinct and order by see
the rows exactly as the reference’s Proxy array shows them. A Value has
no identity or laziness of its own, so this is the port of that handle.