I was able to sort out one of the problems. The historyset is done in one column and I was setting in sequence, by time each row. The problem is that after setting the first row and going into the second row I was going back in time so that was the issue.
To solve the problem I had to collect first all the sets and order them by time. Now the sets don’t go from row to row but instead randomly due to the nature of the order.

What happens now is that I can see the trend graph but only after a while and not consistently. It takes time to load it. It says loading and then turns into a white canvas. Only after a couple of minutes I can see the information but again, it’s not consistently.

The resolution of each value set is of 100ms difference. For each row I get a string with the values and the starting time of the first record. I then just have to add 100ms to each next value and add it into the list.

If anyone wants I can show the element.

Primary key that was being used: “100.212.1.64.EBUR128_M”.
MySQL database stores it like above but when requesting the trend data it is requesting it in small letters like this: “100.212.1.64.ebur128_m”.
That is why I was not able to see trending information.
I’ve changed the key into “100.212.1.64.1” or “100.212.1.64.2” because there are 2 types: “EBUR128_M” and “EBUR128_I”