Practice / strings dates nulls
A blog platform stores each post's tags as a comma-separated string (e.g. "spark,python"). The team wants a tag leaderboard.
posts
Your task: return each individual tag and uses — how many posts use it.
Assign your answer DataFrame to result. Row order doesn't matter.
postsinput DataFrame| column | type |
|---|---|
| post_id | long |
| tags | string |
| post_id | tags |
|---|---|
| 1 | spark,python |
| 2 | python |
| 3 | spark,rust |
taguses· 3 rowsF.split(F.col("tags"), ",") turns the string into an array; F.explode(...)
makes one row per element. Then groupBy("tag") and count("*").
This problem builds on Reshaping Data (~7 min). Pop it open in a new tab if you want a quick recap.