How to use PEEK-function with condition?

[rennesia]

In my application, I want to fill unknown datafields with historical values from the last row with the same TagID (first column). In the actual situation the positions with the red values are empty. I filled in the red values to show what they should be.

A normal PEEK-function can use the data from a fixed previous record, but how to program the condition to copy from a previous record with a certain condition?

[felipedl · Accepted solution]

Hi,

For the peek to work, you'll have to order your data.

In this case, order it by TagID and TimeStamp so you can have a table with the historic view, by TagID. like so:

orderedTable:

Load *,

         if(peek(TagID)=TagID,peek(MTBF),MTBF) as MTBF

Resident dataTable

order by TagID,TimeStamp;

Next, you use the peek() statement to check something like this:

if(peek(TagID)=TagID,peek(MTBF),MTBF)

this if will verify if the previous tag ID is the same as the current one and then get the according MTBG value.

Hope it helps,

Felipe.

[rennesia]

Almost an too easy solution, but it works fine! Thanks Felip!

[felipedl]

Glad it helped