fix: delete logic improved

sql/migrations/000001_init.up.sql

@@ -28,8 +28,8 @@ CREATE TABLE reviews (
     id                  bigint              GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
     data                text                NOT NULL,
     rating              int                 CHECK (rating >= 0 AND rating <= 10),
-    user_id             bigint              REFERENCES users (id),
+    user_id             bigint              REFERENCES users (id) ON DELETE SET NULL,
-    title_id            bigint              REFERENCES titles (id),
+    title_id            bigint              REFERENCES titles (id) ON DELETE CASCADE,
     created_at          timestamptz         DEFAULT NOW()
 );
 
@@ -41,20 +41,20 @@ CREATE TABLE review_images (
 
 CREATE TABLE users (
     id                  bigint              GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
-    avatar_id           bigint              REFERENCES images (id),
+    avatar_id           bigint              REFERENCES images (id) ON DELETE SET NULL,
     passhash            text                NOT NULL,
     mail                text                CHECK (mail ~ '^[a-zA-Z0-9._-]+@[a-zA-Z0-9._-]+\.[a-zA-Z0-9_-]+$'),
     nickname            text                UNIQUE NOT NULL CHECK (nickname ~ '^[a-zA-Z0-9_-]{3,}$'),
     disp_name           text,
     user_desc           text,
-    creation_date       timestamptz         NOT NULL,
+    creation_date       timestamptz         NOT NULL DEFAULT NOW(),
     last_login          timestamptz
 );
 
 CREATE TABLE studios (
     id                  bigint              GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
     studio_name         text                NOT NULL UNIQUE,
-    illust_id           bigint              REFERENCES images (id),
+    illust_id           bigint              REFERENCES images (id) ON DELETE SET NULL,
     studio_desc         text
 );
 
@@ -64,7 +64,7 @@ CREATE TABLE titles (
     -- example {"ru": ["Атака титанов", "Атака Титанов"],"en": ["Attack on Titan", "AoT"],"ja": ["進撃の巨人", "しんげきのきょじん"]}
     title_names         jsonb               NOT NULL,
     studio_id           bigint              NOT NULL REFERENCES studios (id),
-    poster_id           bigint              REFERENCES images (id),
+    poster_id           bigint              REFERENCES images (id) ON DELETE SET NULL,
     title_status        title_status_t      NOT NULL,                          
     rating              float               CHECK (rating >= 0 AND rating <= 10),
     rating_count        int                 CHECK (rating_count >= 0),
@@ -82,19 +82,19 @@ CREATE TABLE titles (
 
 CREATE TABLE usertitles (
                                             PRIMARY KEY (user_id, title_id),
-    user_id             bigint              NOT NULL REFERENCES users (id),
+    user_id             bigint              NOT NULL REFERENCES users (id) ON DELETE CASCADE,
-    title_id            bigint              NOT NULL REFERENCES titles (id),
+    title_id            bigint              NOT NULL REFERENCES titles (id) ON DELETE CASCADE,
     status              usertitle_status_t  NOT NULL,
     rate                int                 CHECK (rate > 0 AND rate <= 10),
-    review_id           bigint              REFERENCES reviews (id),
+    review_id           bigint              REFERENCES reviews (id) ON DELETE SET NULL,
     ctime               timestamptz         NOT NULL DEFAULT now()
     -- // TODO: series status
 );
 
 CREATE TABLE title_tags (
                                             PRIMARY KEY (title_id, tag_id),
-    title_id            bigint              NOT NULL REFERENCES titles (id),
+    title_id            bigint              NOT NULL REFERENCES titles (id) ON DELETE CASCADE,
-    tag_id              bigint              NOT NULL REFERENCES tags (id)
+    tag_id              bigint              NOT NULL REFERENCES tags (id) ON DELETE CASCADE
 );
 
 CREATE TABLE signals (
@@ -180,6 +180,6 @@ END;
 $$ LANGUAGE plpgsql;
 
 CREATE TRIGGER set_ctime_on_update
-BEFORE UPDATE ON usertitles
+AFTER UPDATE ON usertitles
 FOR EACH ROW
 EXECUTE FUNCTION set_ctime();