Good — this helps pinpoint the issue exactly 👍

Your current policy:

```sql
alter policy "Users can insert their own posts"
on "public"."posts"
to public
with check (
  (auth.uid() = author_id)
);
```

---

# 🚨 What’s wrong (2 key problems)

## ❌ 1. `TO public`

* `public` = **anyone (even not logged in)**
* But `auth.uid()` only works for **authenticated users**

👉 This creates a mismatch → policy fails

---

## ❌ 2. Column mismatch (`author_id` vs your code)

Earlier we used:

```sql
user_id
```

Now your policy uses:

```sql
author_id
```

👉 If your insert is sending `user_id` but policy checks `author_id`
→ ❌ **RLS blocks it**

---

# ✅ Fix (Clean & Correct)

## Option A (Recommended — use `author_id`)

If your table uses `author_id`, then fix policy like this:

```sql
ALTER POLICY "Users can insert their own posts"
ON public.posts
TO authenticated
WITH CHECK (auth.uid() = author_id);
```

---

## Option B (If your column is `user_id`)

```sql
ALTER POLICY "Users can insert their own posts"
ON public.posts
TO authenticated
WITH CHECK (auth.uid() = user_id);
```

---

# 🔥 MOST IMPORTANT: Match your code

Your insert MUST match the column:

### If using `author_id`:

```js
await supabase.from('posts').insert([
  {
    title,
    content,
    author_id: user.id // ✅ MUST match policy
  }
])
```

---

# 🧪 Quick Debug Checklist

* [ ] Is user logged in?
* [ ] Column name matches? (`author_id` vs `user_id`)
* [ ] Policy uses `TO authenticated` (NOT public)
* [ ] Insert includes that column

---

# ⚡ Fast Test (to confirm issue)

Temporarily run:

```sql
ALTER POLICY "Users can insert their own posts"
ON public.posts
TO authenticated
WITH CHECK (true);
```

👉 If it works → issue is 100% column mismatch

---

# 🧠 Final Answer

✔ Your policy exists — good
❌ But:

* Wrong role (`public`)
* Possible column mismatch

👉 Fix those → error gone instantly

---

If you want, paste your:

* `posts` table structure
* `createPost` code

I’ll align everything perfectly so it just works 👍


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