Improved update performance of water_name layer
- Implemented diff updates for update_water_lakeline.sql and update_water_point.sql
- Unified update_water_lakeline.sql and update_water_point.sql to update_water_name.sql
- Refactored IDs to be unique in water_name_marine.osm_ids
- Restricted updates to INSERT and UPDATE operations during water_name_marine.refresh
- Added analyze statements before update queries during water_name_marine.refresh
Replacing update on the whole table with an update only on changed rows.
The goal is to update more quickly by just updating the changing content.
The update now focus on osm_id of changed rows, it use index. Add a where clause tags != update_tags(tags, geometry) to ensure only update when changed.
It requires one more trigger and a table to store changed osm_id.
The UPDATE is keep in a function to be reusable for initial setup and trigger update.
It is a based on the already merged https://github.com/openmaptiles/openmaptiles/pull/944
It is a separated PR as less obvious than previous. It replaces the reset of the `rank` field to NULL by missing value resulting of `LEFT JOIN`. It avoid triggering a new update on the table by reset the value then re-seting it to initial or new value.
It addresses #814.
Thanks @frodrigo
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`.
Peter Hanecak