SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e41b82e80b2838494d8c99b4b08eebbc3c12f898498db0eba8c828a2049c083a' 
  AND token = '1p3T6lIcrWwMKfySQVQKPHv4m1A2ws6T1GPIbWTkkWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}