Lesson 2.1.7
Column dependencies: how one column waits for the one it reads
What this costs
Free. Dependencies are set for you when the column is created.
Before you start
Any workflow where one column reads another.
When a tool column reads another column, Kuration records that as a dependency on the column. You do not set it up yourself: creating the column adds it, pointing at the columns the tool takes as inputs. It is why a people column built on a website column does not run ahead of it.
The two switches on a dependency
| Setting | What it does | Default |
|---|---|---|
| Run before | The column being read goes first on each row, so this column never reads a value that has not arrived yet | On |
| Skip if invalid | If the input on a row is empty or unusable, the row is marked Skipped instead of being run on nothing | On |
Together they let you build the stack in one go. Website Finder, then a qualifier that reads the website, then a people search that reads both: each column waits for the ones it depends on, and a row with no website is skipped by the people search rather than run on a blank.
Where to see them
Open the column configuration. Dependencies sit next to Conditions, and both travel with the column rather than with your view, so a new batch of rows or a scheduled refresh follows the same order.
A column shows a lot of Skipped rows
- What you see
- Coverage looks low and there is no error anywhere
- The fix
- Read the skip reason. If the input it depends on is empty on those rows, fill that column first, then run the skipped rows.
Judged a column finished from the visible rows
- What you see
- The first hundred rows look done, the rest are still running
- The fix
- Check the column status or Project Analytics across the whole table.
Ran the whole column again to fill a few rows
- What you see
- Worried the finished rows were charged twice
- The fix
- They were not. A normal run only fills empty cells. Filled cells, Not Found included, are left alone unless you choose otherwise under Advanced Options.
You have finished the expensive part
Website first, conditions on everything, a waterfall where it pays, a custom column with a forced format, checks only where being wrong is costly, and every empty looking cell read for what it is. That is the whole cost discipline. Next comes making the cut defensible, which is scoring.
Check yourself
0 of 2 answered1.You add a people column that reads the website column. Who sets up the dependency between them?
2.A column needs another column to have run first. What makes that happen?
Try it yourself
Open the configuration of a tool column that reads another column and find its Dependencies. Note which column it waits for, and whether run before and skip if invalid are on.
- You have done it when
- You can name the column each tool column in your table depends on, and point to a row it skipped because that input was empty.
- Credit budget
- Free.