Testing Columns
Column tests are meant to check for null and unique values, and are always run after transformations. This cannot be changed unless using a user-defined node.
Example Column Test
- Click on Testing → Column.
- Select both Unique and Null.
![Example Column Test](https://files.readme.io/fcb91e6-example_column_test.png)
Example column test
- Now click on Null next to
C_NATIONKEY
. This will check to ensure all entries for this column are populated (not null). - Run the node and it should succeed, as there's no null entries.
![Successful column test](https://files.readme.io/135d17a-column_test_null.png)
Successful column test
- Now try also selecting Unique for the
C_NATIONKEY
column. This will check to ensure all entries for this column are unique. - Run the node and it will fail, as
C_NATIONKEY
has repeated entries. Notice that the data was still processed, as column tests will always continue on failure.
![Failed column test](https://files.readme.io/b8be89b-column_test_unique.png)
Failed column test
Updated 3 months ago