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range_probes

Function range_probes 

Source
fn range_probes(q: &Search) -> Vec<Probe>
Expand description

The comparisons in a search that a zone map can answer.

Only an unquoted number qualifies, and that is a rule about the scan rather than about the index. A quoted scalar means a text comparison on a str-typed attribute (see AttrPred) and a numeric one on an int column, so the same term is lexicographic against one row and arithmetic against the next — two orderings, and crate::zone describes one. Since an absent key is read as “prune”, a probe that describes the wrong ordering would not merely mislead, it would drop rows. Ne and Contains are out for the reason in crate::zone: they prune nothing worth the branch.