Merge pull request #61 from konturio/21258-add-coverage-generation-and-indicators-coverage-endpoint-to-insights-api

update find_max_resolution: set coverage polygon

Author: sleeping-h

procedures/find_max_resolution.sql

@@ -7,6 +7,8 @@ $$
 declare
     area_km2_uuid uuid;
     one_uuid uuid;
+    global_max_res integer;
+    coverage_max_res integer;
 begin
 
     select internal_id into area_km2_uuid
@@ -22,11 +24,32 @@ begin
         return;
     end if;
 
-    update bivariate_indicators_metadata
-    set max_res = (
-        select max(h3_get_resolution(h3))
+    with resolution_counts as (
+        select
+            h3_get_resolution(h3) as res,
+            count(9) as cnt
         from stat_h3_transposed
         where indicator_uuid = x_numerator_uuid
+        group by 1
+    ),
+    global as (
+        select max(res) as r from resolution_counts
+    ),
+    coverage as (
+        select max(res) as r from resolution_counts where cnt <= 1000
+    )
+    select global.r, coverage.r
+    into global_max_res, coverage_max_res
+    from global, coverage;
+
+    update bivariate_indicators_metadata
+    set
+        max_res = global_max_res,
+        coverage_polygon = (
+            select ST_Transform(ST_Union(h3_cell_to_boundary_geometry(h3)), 4326)
+            from stat_h3_transposed
+            where indicator_uuid = x_numerator_uuid
+              and h3_get_resolution(h3) = coverage_max_res
     )
     where internal_id = x_numerator_uuid;