SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '403087cd40feeea3142ab66670e1312328a23ad7df397b22588a66fda1ee8eee' 
  AND token = 'nrsWIXKzfYMggPxyB1AQrAY5H7xso0r0c8m8ZnaxmAc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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