Materialize record releases to improve performance

priv/repo/migrations/20260216121934_create_record_releases.exs

@@ -0,0 +1,79 @@
+defmodule MusicLibrary.Repo.Migrations.CreateRecordReleases do
+  use Ecto.Migration
+
+  def up do
+    execute """
+    CREATE TABLE record_releases (
+      record_id TEXT NOT NULL,
+      release_id TEXT NOT NULL,
+      cover_hash TEXT,
+      purchased_at TEXT,
+      PRIMARY KEY (record_id, release_id),
+      FOREIGN KEY (record_id) REFERENCES records(id) ON DELETE CASCADE
+    );
+    """
+
+    execute """
+    CREATE INDEX record_releases_release_id_index ON record_releases(release_id);
+    """
+
+    flush()
+
+    # Populate from existing data
+    execute """
+    INSERT INTO record_releases (record_id, release_id, cover_hash, purchased_at)
+    SELECT records.id, json_each.value, records.cover_hash, records.purchased_at
+    FROM records, json_each(records.release_ids);
+    """
+
+    flush()
+
+    # Trigger: after insert on records, expand release_ids into record_releases
+    execute """
+    CREATE TRIGGER record_releases_after_insert
+    AFTER INSERT ON records
+    BEGIN
+      INSERT INTO record_releases (record_id, release_id, cover_hash, purchased_at)
+      SELECT NEW.id, json_each.value, NEW.cover_hash, NEW.purchased_at
+      FROM json_each(NEW.release_ids);
+    END;
+    """
+
+    # Trigger: before update on records, remove old rows
+    execute """
+    CREATE TRIGGER record_releases_before_update
+    BEFORE UPDATE ON records
+    BEGIN
+      DELETE FROM record_releases WHERE record_id = OLD.id;
+    END;
+    """
+
+    # Trigger: after update on records, insert new rows
+    execute """
+    CREATE TRIGGER record_releases_after_update
+    AFTER UPDATE ON records
+    BEGIN
+      INSERT INTO record_releases (record_id, release_id, cover_hash, purchased_at)
+      SELECT NEW.id, json_each.value, NEW.cover_hash, NEW.purchased_at
+      FROM json_each(NEW.release_ids);
+    END;
+    """
+
+    # Trigger: before delete on records, remove rows
+    execute """
+    CREATE TRIGGER record_releases_before_delete
+    BEFORE DELETE ON records
+    BEGIN
+      DELETE FROM record_releases WHERE record_id = OLD.id;
+    END;
+    """
+  end
+
+  def down do
+    execute "DROP TRIGGER IF EXISTS record_releases_after_insert"
+    execute "DROP TRIGGER IF EXISTS record_releases_before_update"
+    execute "DROP TRIGGER IF EXISTS record_releases_after_update"
+    execute "DROP TRIGGER IF EXISTS record_releases_before_delete"
+    execute "DROP TABLE IF EXISTS record_releases"
+  end
+end