On creation of materialized views `osm_transportation_merge_linestring_gen_zX`, an index is created each time the new view and not used else where than the next generalization step.
It does not worth it to to a scan on the table to create index that will be used only once, while the next generalisation step can also be done in one full scan.
So, removing these indices.
The index `osm_highway_linestring_highway_idx` is not used. There is also a used partial index `osm_highway_linestring_highway_partial_idx`.
I cross check the usage of the index from postgres query stats and all SQL query code where the table `osm_highway_linestring` is refered.
This index is relatively big.
I would like to reformat all of our SQL to have a concise coding style.
This makes it far easier to understand the code for a casual contributor,
and lets us spot errors more easily.
Most importantly, it makes it much easier to grep (search) the code because it is more likely to be in the same syntax
Some key changes:
* SQL keywords are always UPPERCASE, e.g. `SELECT WHEN AS END ...`
* types, variables, aliases, and field names (identifiers) are always lower case
* `LANGUAGE 'plpgsql'` is now `LANGUAGE plpgsql` (no quotes)
* a few minor spacing/semicolon cleanups
P.S. Per @TomPohys request, `TABLE` is spelled using upper case despite being a type for consistency with PG Docs. Same for `LANGUAGE SQL` vs `LANGUAGE plpgsql`.
Tag all SQL materialized views with a machine-readable comment
to indicate that this materialized view can be created without
data:
/* DELAY_MATERIALIZED_VIEW_CREATION */
In the next version of tools this comment can be optionally
replaced with the "WITH NO DATA" parameter, thus allowing
a much faster execution of the SQL script. All materialized
viewes will be populated with data in parallel afterwards
using the `refresh-views` tools script.