i wants to add 2nd constraint in my Model below, what is the best correct way or method to do so.

(''check_price, 'CHECK(price >= 0)', 'The value of Inquiry -> Price can\'t be negative.'),

from odoo import models, fields

class CRMLeadsInquiry(models.Model):

    _inherit = "crm.lead"

    product_id = fields.Many2one('product.product', string='Product Name', required=False)

    qty = fields.Integer(string='Quantity', default=1)

   price = fields.Float(string='Price', default=1)

    _sql_constraints = [

            ('check_qty', 'CHECK(qty >= 0)', 'The value of Inquiry -> Quantity can\'t be negative.'),

    ]

note: if it can be, how many i _sql_constraints i can add? is there any limitations?

regards