I have a table with a quantity column, defined as DECIMAL(8,3).

I wrote a test that creates a record in the table and tests if the record is present:

$this->assertDatabaseHas('my_table', [
    'id' => $newRecord->getKey(),
    'id_user' => $id_user,
    'quantity' => (float)$quantity,
    'id_action' => 5,
]);

This is the result of the test:

Failed asserting that a row in the table [my_table] matches the attributes {
    "id_user": 6166,
    "quantity": 10,
    "id_action": 5,
    "params": "{"id_sale_bid":2040}"
}.

Found similar results: [
    {
        "id_user": 6166,
        "quantity": "10.000",
        "id_action": 5,
        "params": "{"id_sale_bid": 2040}"
    }
]

As you can see the record is present, it’s just that it looks for the wrong type.