SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6835b07823b1df610c191d9fc2137e6cccfe60656cf241d4d682439835b4fe89' 
  AND token = 'VZOZRX5lD3UHTpj7CndfyIcVjxw09lQerKCeUocBuBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}