Remove unused osm_transportation_merge_linestring table (#1171)

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PR #1168 removed several `WHERE` clauses in the `transportation_merge_*` table series.  With those removed, it appears that `osm_transportation_merge_linestring_gen_z8` and `osm_transportation_merge_linestring` are nearly identical, with the former simply adding an `ST_Simplify()` operation.

A grep of the codebase indicates that the _only_ use for `osm_transportation_merge_linestring` is to hold the intermediate result of an `ST_Dump(geometry))` before it is fed into `ST_Simplify()`.  Therefore, it appears that we're holding an entire zoom 8 copy of the transportation layer (all motorway/trunk/primary roads) in a materialized view for absolutely no reason at all.

This PR removes the `osm_transportation_merge_linestring` intermediate table and changes the definition of `osm_transportation_merge_linestring_gen_z8` to perform the `ST_Dump()` and `ST_Simplify()` transformations directly from the `osm_highway_linestring` table in a single operation.

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This commit is contained in:

Brian Sperlongano

2021-08-11 04:46:17 -04:00

committed by GitHub

parent 09078f6d7d

commit f78d42ec84

2 changed files with 4 additions and 24 deletions

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