diff --git a/scripts/add-materi-documents.sql b/scripts/add-materi-documents.sql
index 5361a6a..19b99ea 100644
--- a/scripts/add-materi-documents.sql
+++ b/scripts/add-materi-documents.sql
@@ -1,27 +1,29 @@
 -- Migration: Add materi_documents table for learning materials + RAG
 -- Run: PGPASSWORD=<pw> psql -h <host> -U <user> -d <db> -f scripts/add-materi-documents.sql
+-- Schema mirrors services/backend/src/shared/database/schema.ts (pgMateriDocumentsTable).
 
 BEGIN;
 
-CREATE TABLE IF NOT EXISTS "materi_documents" (
-  "id" uuid PRIMARY KEY DEFAULT gen_random_uuid(),
-  "title" text NOT NULL,
-  "description" text,
-  "content" text NOT NULL,
-  "category" text NOT NULL DEFAULT 'general',
-  "tags" jsonb NOT NULL DEFAULT '[]',
-  "owner_user_id" text NOT NULL DEFAULT 'anonymous',
-  "guild_id" text,
-  "channel_id" text,
-  "is_public" boolean NOT NULL DEFAULT true,
-  "view_count" integer NOT NULL DEFAULT 0,
-  "created_at" bigint NOT NULL DEFAULT extract(epoch from now())::bigint,
-  "updated_at" bigint NOT NULL DEFAULT extract(epoch from now())::bigint
+CREATE TABLE IF NOT EXISTS public.materi_documents (
+    id            uuid          PRIMARY KEY DEFAULT gen_random_uuid(),
+    title         text          NOT NULL,
+    description   text,
+    content       text          NOT NULL,
+    category      text          NOT NULL DEFAULT 'general',
+    tags          jsonb         NOT NULL DEFAULT '[]',
+    owner_user_id text          NOT NULL DEFAULT 'anonymous',
+    guild_id      text,
+    channel_id    text,
+    is_public     boolean       NOT NULL DEFAULT true,
+    view_count    integer       NOT NULL DEFAULT 0,
+    created_at    bigint        NOT NULL DEFAULT (EXTRACT(epoch FROM now())::bigint * 1000),
+    updated_at    bigint        NOT NULL DEFAULT (EXTRACT(epoch FROM now())::bigint * 1000)
 );
 
-CREATE INDEX IF NOT EXISTS "idx_materi_category" ON "materi_documents" ("category");
-CREATE INDEX IF NOT EXISTS "idx_materi_is_public" ON "materi_documents" ("is_public");
-CREATE INDEX IF NOT EXISTS "idx_materi_owner" ON "materi_documents" ("owner_user_id");
-CREATE INDEX IF NOT EXISTS "idx_materi_created" ON "materi_documents" ("created_at");
+-- Indexes mirror the Drizzle index definitions (idx_materi_category, idx_materi_owner, idx_materi_guild, idx_materi_search).
+CREATE INDEX IF NOT EXISTS idx_materi_category ON public.materi_documents (category);
+CREATE INDEX IF NOT EXISTS idx_materi_owner    ON public.materi_documents (owner_user_id);
+CREATE INDEX IF NOT EXISTS idx_materi_guild    ON public.materi_documents (guild_id);
+CREATE INDEX IF NOT EXISTS idx_materi_search   ON public.materi_documents (title, category);
 
 COMMIT;
diff --git a/services/backend/src/shared/database/schema.ts b/services/backend/src/shared/database/schema.ts
index 473e7a8..d20c63a 100644
--- a/services/backend/src/shared/database/schema.ts
+++ b/services/backend/src/shared/database/schema.ts
@@ -616,7 +616,7 @@ export const pgMateriDocumentsTable = pgTable(
     description: pgText("description"),
     content: pgText("content").notNull(),
     category: pgText("category").notNull().default("general"),
-    tags: pgText("tags").array(),
+    tags: pgJsonb("tags").notNull().default("[]"),
     owner_user_id: pgText("owner_user_id").notNull(),
     guild_id: pgText("guild_id"),
     channel_id: pgText("channel_id"),