Practice / nulls and conditions
The Daily Grind's loyalty program can only email customers who left an address.
contacts
Your task: return the id and email of every contact that has an email (a non-null value).
Assign your answer DataFrame to result. Row order doesn't matter.
contactsinput DataFrame| column | type |
|---|---|
| id | long |
| string |
| id | |
|---|---|
| 1 | a@x.com |
| 2 | null |
| 3 | c@x.com |
| 4 | null |
idemail· 2 rowsTest for a present value with F.col("email").isNotNull() (never != None —
a comparison to null is null, not true). Then select("id", "email").
This problem builds on Null Is Not a Value (~4 min). Pop it open in a new tab if you want a quick recap.