Make sure that the cached Job build status is always synchronized.

* src/sql/upgrade-10.sql: New file.
* Makefile.am (dist_sql_DATA): Update it.
* src/schema.sql (update_job_status): New function,
(build_status): new trigger.

Makefile.am

@@ -96,7 +96,8 @@ dist_sql_DATA = 				\
   src/sql/upgrade-6.sql				\
   src/sql/upgrade-7.sql				\
   src/sql/upgrade-8.sql				\
-  src/sql/upgrade-9.sql
+  src/sql/upgrade-9.sql				\
+  src/sql/upgrade-10.sql
 
 dist_css_DATA =					\
   src/static/css/choices.min.css		\

src/schema.sql

@@ -131,6 +131,20 @@ CREATE INDEX Builds_status_ts_id on Builds(status DESC, timestamp DESC, id ASC);
 CREATE INDEX Builds_priority_timestamp on Builds(priority ASC, timestamp DESC);
 CREATE INDEX Builds_weather_evaluation ON Builds (weather, evaluation);
 
+-- Make sure that the cached Job build status is always synchronized with the
+-- matching build status.
+CREATE FUNCTION update_job_status()
+RETURNS TRIGGER AS $$
+BEGIN
+UPDATE Jobs SET status = NEW.status WHERE Jobs.build = NEW.id;
+RETURN null;
+END
+$$ LANGUAGE plpgsql;
+
+CREATE TRIGGER build_status AFTER UPDATE ON Builds
+FOR EACH ROW
+EXECUTE PROCEDURE update_job_status();
+
 CREATE INDEX Jobs_name ON Jobs (name);
 CREATE INDEX Jobs_system_status ON Jobs (system, status);
 CREATE INDEX Jobs_build ON Jobs (build); --speeds up delete cascade.

src/sql/upgrade-10.sql

@@ -0,0 +1,17 @@
+BEGIN TRANSACTION;
+
+-- Make sure that the cached Job build status is always synchronized with the
+-- matching build status.
+CREATE FUNCTION update_job_status()
+RETURNS TRIGGER AS $$
+BEGIN
+UPDATE Jobs SET status = NEW.status WHERE Jobs.build = NEW.id;
+RETURN null;
+END
+$$ LANGUAGE plpgsql;
+
+CREATE TRIGGER build_status AFTER UPDATE ON Builds
+FOR EACH ROW
+EXECUTE PROCEDURE update_job_status();
+
+COMMIT;