Laravel Unique Validation: Handling Updates and Soft Deletes

The basic unique validation rule works fine for a create form, but two very common real situations break its default behavior — editing an existing record, and soft-deleted rows that should arguably no longer "hold" a unique value.

1. The basic rule

$request->validate([
    'email' => 'required|email|unique:users,email',
]);

2. The update problem: a record fails uniqueness against itself

Editing a user and resubmitting the form without changing their email fails this exact rule — the database genuinely does already have a row with that email address: the row being edited. Without accounting for this, every edit of an unchanged unique field incorrectly reports "this email is already taken."

$request->validate([
    'email' => 'required|email|unique:users,email,' . $user->id,
]);

The third parameter tells the rule to ignore a specific row's ID when checking for a conflict — this excludes the record currently being edited from the uniqueness check, so only a genuinely different row sharing that email triggers a failure.

3. The same thing using the Rule class (the more explicit, less error-prone form)

use Illuminate\Validation\Rule;

$request->validate([
    'email' => [
        'required',
        'email',
        Rule::unique('users', 'email')->ignore($user->id),
    ],
]);

The string-based syntax above works but is easy to get subtly wrong (a mistyped column name in the wrong position in the comma-separated string fails silently rather than throwing an error) — Rule::unique() expresses the same ignore logic more explicitly and is generally the safer choice, especially once more conditions get added.

4. The soft-delete problem

By default, a plain unique rule checks the raw database table, including soft-deleted rows — so a soft-deleted user's email still counts as "taken," blocking a new signup with that same address even though the original account is, from the application's perspective, gone. Whether that's correct behavior is a real product decision, not a bug — some apps want deleted users' emails permanently reserved; many don't.

Rule::unique('users', 'email')
    ->ignore($user->id)
    ->whereNull('deleted_at'); // only counts against still-active rows

->whereNull('deleted_at') excludes soft-deleted rows from the uniqueness check entirely, so a new signup can reuse an email that only exists on a soft-deleted account. This needs to be added deliberately — it isn't the default behavior — because Laravel's unique rule doesn't automatically know a table uses soft deletes.

5. Scoping uniqueness to a subset — unique within a tenant, not globally

Rule::unique('products', 'sku')
    ->where('site_id', $siteId)
    ->ignore($product->id);

For multi-tenant data where a value only needs to be unique within one tenant's scope (a SKU unique per store, not globally across every store in the database), an additional ->where() constraint narrows the uniqueness check to just that tenant's rows — otherwise the rule checks uniqueness across the entire table regardless of tenant.

6. Combining all three together

Rule::unique('products', 'sku')
    ->where('site_id', $siteId)
    ->ignore($product->id)
    ->whereNull('deleted_at');

These conditions compose freely — a real-world unique rule on an editable, soft-deletable, multi-tenant field commonly needs all three at once, and each addresses a genuinely distinct edge case that the bare unique rule alone doesn't handle correctly.