From ca8dd68d1044b7e815ac4a4169b5a4425dfbf438 Mon Sep 17 00:00:00 2001
From: "D. Berge" <dberge@aaltronav.eu>
Date: Thu, 2 Nov 2023 11:54:03 +0100
Subject: [PATCH] Add database upgrade file 32.

---
 ...0.4.5-materialise-view-project_summary.sql | 147 ++++++++++++++++++
 1 file changed, 147 insertions(+)
 create mode 100644 etc/db/upgrades/upgrade32-v0.4.5-materialise-view-project_summary.sql

diff --git a/etc/db/upgrades/upgrade32-v0.4.5-materialise-view-project_summary.sql b/etc/db/upgrades/upgrade32-v0.4.5-materialise-view-project_summary.sql
new file mode 100644
index 0000000..74fc2ff
--- /dev/null
+++ b/etc/db/upgrades/upgrade32-v0.4.5-materialise-view-project_summary.sql
@@ -0,0 +1,147 @@
+-- Turn project_summary into a materialised view
+--
+-- New schema version: 0.4.5
+--
+-- ATTENTION:
+--
+-- ENSURE YOU HAVE BACKED UP THE DATABASE BEFORE RUNNING THIS SCRIPT.
+--
+--
+-- NOTE: This upgrade affects all schemas in the database.
+-- NOTE: Each application starts a transaction, which must be committed
+-- or rolled back.
+--
+-- The project_summary view is quite a bottleneck. While it itself is
+-- not the real culprit (rather the underlying views are), this is one
+-- relatively cheap way of improving responsiveness from the client's
+-- point of view.
+-- We leave the details of how / when to refresh the view to the non-
+-- database code.
+--
+-- To apply, run as the dougal user:
+--
+-- psql <<EOF
+-- \i $THIS_FILE
+-- COMMIT;
+-- EOF
+--
+-- NOTE: It can be applied multiple times without ill effect.
+--
+
+BEGIN;
+
+CREATE OR REPLACE PROCEDURE pg_temp.show_notice (notice text) AS $$
+BEGIN
+	RAISE NOTICE '%', notice;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE PROCEDURE pg_temp.upgrade_survey_schema (schema_name text) AS $outer$
+BEGIN
+
+	RAISE NOTICE 'Updating schema %', schema_name;
+	-- We need to set the search path because some of the trigger
+	-- functions reference other tables in survey schemas assuming
+	-- they are in the search path.
+	EXECUTE format('SET search_path TO %I,public', schema_name);
+
+	DROP VIEW project_summary;
+
+	CREATE MATERIALIZED VIEW project_summary AS
+	WITH fls AS (
+		SELECT
+			avg((final_lines_summary.duration / ((final_lines_summary.num_points - 1))::double precision)) AS shooting_rate,
+			avg((final_lines_summary.length / date_part('epoch'::text, final_lines_summary.duration))) AS speed,
+			sum(final_lines_summary.duration) AS prod_duration,
+			sum(final_lines_summary.length) AS prod_distance
+		FROM final_lines_summary
+	), project AS (
+		SELECT
+			p.pid,
+			p.name,
+			p.schema
+		FROM public.projects p
+		WHERE (split_part(current_setting('search_path'::text), ','::text, 1) = p.schema)
+	)
+	SELECT
+		project.pid,
+		project.name,
+		project.schema,
+		( SELECT count(*) AS count
+			FROM preplot_lines
+			WHERE (preplot_lines.class = 'V'::bpchar)) AS lines,
+		ps.total,
+		ps.virgin,
+		ps.prime,
+		ps.other,
+		ps.ntba,
+		ps.remaining,
+		( SELECT to_json(fs.*) AS to_json
+			FROM final_shots fs
+			ORDER BY fs.tstamp
+			LIMIT 1) AS fsp,
+		( SELECT to_json(fs.*) AS to_json
+			FROM final_shots fs
+			ORDER BY fs.tstamp DESC
+			LIMIT 1) AS lsp,
+		( SELECT count(*) AS count
+			FROM raw_lines rl) AS seq_raw,
+		( SELECT count(*) AS count
+			FROM final_lines rl) AS seq_final,
+		fls.prod_duration,
+		fls.prod_distance,
+		fls.speed AS shooting_rate
+	FROM preplot_summary ps,
+		fls,
+		project;
+
+END;
+$outer$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE PROCEDURE pg_temp.upgrade () AS $outer$
+DECLARE
+	row RECORD;
+	current_db_version TEXT;
+BEGIN
+
+	SELECT value->>'db_schema' INTO current_db_version FROM public.info WHERE key = 'version';
+
+	IF current_db_version >= '0.4.5' THEN
+		RAISE EXCEPTION
+			USING MESSAGE='Patch already applied';
+	END IF;
+
+	IF current_db_version != '0.4.4' THEN
+		RAISE EXCEPTION
+			USING MESSAGE='Invalid database version: ' || current_db_version,
+				HINT='Ensure all previous patches have been applied.';
+	END IF;
+
+	FOR row IN
+		SELECT schema_name FROM information_schema.schemata
+		WHERE schema_name LIKE 'survey_%'
+		ORDER BY schema_name
+	LOOP
+		CALL pg_temp.upgrade_survey_schema(row.schema_name);
+	END LOOP;
+END;
+$outer$ LANGUAGE plpgsql;
+
+CALL pg_temp.upgrade();
+
+CALL pg_temp.show_notice('Cleaning up');
+DROP PROCEDURE pg_temp.upgrade_survey_schema (schema_name text);
+DROP PROCEDURE pg_temp.upgrade ();
+
+CALL pg_temp.show_notice('Updating db_schema version');
+INSERT INTO public.info VALUES ('version', '{"db_schema": "0.4.5"}')
+ON CONFLICT (key) DO UPDATE
+	SET value = public.info.value || '{"db_schema": "0.4.5"}' WHERE public.info.key = 'version';
+
+
+CALL pg_temp.show_notice('All done. You may now run "COMMIT;" to persist the changes');
+DROP PROCEDURE pg_temp.show_notice (notice text);
+
+--
+--NOTE Run `COMMIT;` now if all went well
+--