Generate index lookups for filters that appear in lateral joins#3380
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Generate index lookups for filters that appear in lateral joins#3380
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This PR enhances the "applyIndexesFromOuterScope" analysis pass to transform filters on tablescans into indexed table lookups, when the table's column is being compared with a column visible from a lateral join.
An example of a query that can be optimized with this change:
select x, u from xy, lateral (select * from uv where y = u) uv;Users don't often write lateral joins, but the engine can transform
WHERE EXISTSexpressions into lateral joins, and this lets us optimize those too.