From 5def84282d867bfbcc2c3e9afaaf7dbe28573aa1 Mon Sep 17 00:00:00 2001
From: Fabrice Lecomte <fabrice.lecomte.be@gmail.com>
Date: Fri, 4 Sep 2020 15:22:15 +0200
Subject: [PATCH] Improve vote count with cache

---
 .../sql/functions/article/find_articles.sql        |  9 +++++----
 src/main/resources/sql/functions/vote/vote.sql     | 13 +++++++++++++
 .../sql/migrations/0000-init_schema.up.sql         | 14 ++++++++++++++
 3 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/src/main/resources/sql/functions/article/find_articles.sql b/src/main/resources/sql/functions/article/find_articles.sql
index eed518b..f9ad471 100644
--- a/src/main/resources/sql/functions/article/find_articles.sql
+++ b/src/main/resources/sql/functions/article/find_articles.sql
@@ -28,6 +28,7 @@ begin
             count_opinion(a.id) as opinions,
             zdb.score(a.ctid) _score
         from article as a
+        left join vote_cache ca using (id)
         where (
               _search is null
            or _search = ''
@@ -43,8 +44,8 @@ begin
             case sort
                 when 'title' then a.title
                 when 'created_at' then a.created_at::text
-                when 'vote' then count_vote(a.id)->>'score'
-                when 'popularity' then count_vote(a.id)->>'total'
+                when 'vote' then ca.score::text
+                when 'popularity' then ca.total::text
                 else null
             end
         end,
@@ -52,8 +53,8 @@ begin
             case sort
                 when 'title' then a.title
                 when 'created_at' then a.created_at::text
-                when 'vote' then count_vote(a.id)->>'score'
-                when 'popularity' then count_vote(a.id)->>'total'
+                when 'vote' then ca.score::text
+                when 'popularity' then ca.total::text
             end
         end
         desc,
diff --git a/src/main/resources/sql/functions/vote/vote.sql b/src/main/resources/sql/functions/vote/vote.sql
index e9ce156..7d7a928 100644
--- a/src/main/resources/sql/functions/vote/vote.sql
+++ b/src/main/resources/sql/functions/vote/vote.sql
@@ -35,6 +35,19 @@ begin
     end if;
 
     select count_vote(_target_id) into resource;
+
+    insert into vote_cache (id, total, score, percent) values
+    (
+        _target_id,
+        (resource->>'total')::int,
+        (resource->>'score')::int,
+        (resource->>'percent')::int
+    )
+    on conflict (id) do update set
+        updated_at = now(),
+        total = excluded.total,
+        score = excluded.score,
+        percent = excluded.percent;
 end;
 $$;
 
diff --git a/src/main/resources/sql/migrations/0000-init_schema.up.sql b/src/main/resources/sql/migrations/0000-init_schema.up.sql
index d170490..5d09de6 100644
--- a/src/main/resources/sql/migrations/0000-init_schema.up.sql
+++ b/src/main/resources/sql/migrations/0000-init_schema.up.sql
@@ -495,6 +495,20 @@ create table vote_for_comment_on_constitution
     unique (created_by_id, target_id)
 ) inherits (vote);
 
+
+create table vote_cache
+(
+    id         uuid      not null primary key,
+    updated_at timestamp not null default now(),
+    total      int       not null default 0,
+    score      int       not null default 0,
+    percent    int       not null default 0
+);
+
+create index on vote_cache (total);
+create index on vote_cache (score);
+create index on vote_cache (percent);
+
 -- Stats
 create table resource_view
 (