Adding rows with the same value until a condition is met

[MarvEw1111]

The following problem:

We have a time series, which we subtract from the DB. The data is available in such a way that a new value is only saved when there is a change in a column. Now I would like to create a complete time series. For this I would have to create a Power Query formula. This should add more rows with the same values until a change occurs. From that point on, the new values should be entered. The steps are in minute increments and the rows should be padded accordingly. Can anyone help me with this?

[artemus]

start by creating a time list:

List.Generate(() => List.Min(myTable[Date]), each _ < List.Mac(myTable[Date]), each _ + #duration(0,0,1,0))

Next, convert the list to a table, and to a left join on that table with your primary table.

Finally, use Fill down to replicate the values in column A and B.