Lua How costly is this kind of operations (SQL)?

[trollebror]

Hello OTLanders!
I'm wondering about exactly how efficient or inefficient is it to use this kind of database operations.

function insertToSQL(accid, time, admin_id, comment)
	return db.executeQuery("INSERT INTO `someDataz` ... ")
end

function getBanAccInfo(acc)
	local info,qry = {},db.getResult("SELECT `someDataz` ...")
	if (qry:getID() ~= -1) then
		info = {qry:getDataInt("expires"), qry:getDataString("comment"), qry:getDataString("admin_id")}
	end
	return info
end

Let's say that one of these functions will get called as often as a rope.lua script would, would it be terrible bad? How would a efficient solution look like? Is there a way to store SQL-data in cache like the getPlayerStorageValue() is doing?