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In the initial cut at the "parameterized paths" feature, I'd simplified create_index_paths() to the point where it would only generate a single parameterized bitmap path per relation. Experimentation with an example supplied by Josh Berkus convinces me that that's not good enough: we really need to consider a bitmap path for each possible outer relation. Otherwise we have regressions relative to pre-9.2 versions, in which the planner picks a plain indexscan where it should have used a bitmap scan in queries involving three or more tables. Indeed, after fixing this, several queries in the regression tests show improved plans as a result of using bitmap not plain indexscans.