In laravel 10/mysql 8 app I have a table with datetime field:

public function up(): void
{
        Schema::create('reactions', function (Blueprint $table) {
        $table->id();
        $table->foreignId('user_id')->nullable()->references('id')->on('users')->onDelete('CASCADE');

        $table->morphs('model');
        $table->unsignedTinyInteger('action');

        $table->timestamp('created_at')->useCurrent();

        $table->unique(['model_type', 'model_id', 'user_id', 'action'], 'reactions_4fields_unique');
        $table->index(['model_type', 'model_id', 'action', 'created_at'], 'reactions_4fields_index');
        $table->index(['created_at', 'model_type', 'model_id'], 'reactions_3fields_index');
    });
}

and running request by date :

$this->reactions = Reaction
    ::query()->whereDate('created_at', $this->filterAtDate)
    ->groupBy('action')
    ->orderBy('reaction_count', 'desc')
    ->select(
        $reactionTb . '.action',
        DB::raw('count(' . $reactionTb . '.id) as reaction_count'))
    ->get()->toArray();

I check explain of the request :

explain   SELECT `reactions`.`action`, count(reactions.id)     AS reaction_count
    FROM `reactions`
    WHERE date(`created_at`) = '2024-05-14 00:00:00'
    GROUP BY `action`
    ORDER BY `reaction_count` desc

and see as created_at is time too “date” method is used and in explain output with
Possible keys:

reactions_4fields_unique,reactions_4fields_index

Key :

reactions_4fields_index

Not sure if indexing of created_at field would work here ? Is whereDate method good here ?
I see decision for latest version for mysql and postgresql…