SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94014faef035b7d69ba09c3734b34415f11e2562233900256d036cf52c978be1' 
  AND token = 'ipczANaWNhwkC+iWXRwnjnJRYhln4Qlz+da+/phO8L4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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