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Home/Questions/Spark/Big Data/Write a PySpark job that calculates the number of unique users who logged in per day, but exclude any logins from inactive users listed in a separate file.

Write a PySpark job that calculates the number of unique users who logged in per day, but exclude any logins from inactive users listed in a separate file.

Spark/Big Datamedium0.3 min readPremium
Frequency
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Asked at 1 company
Category
452
questions in Spark/Big Data
Difficulty Split
88E|81M|283H
in this category
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1,863
across 7 categories
Asked at these companies
Dunnhumby
Key Concepts Tested
joinpartitionpythonsparksql
Expert AnswerPremium
58 wordsIncludes code examplesInterview-ready
**Code**: ```python from pyspark.sql.functions import countDistinct, to_date logins = spark.read.parquet("/logins") inactive = spark.read.text("/inactive_users").selectExpr("value as user_id") active_logins = logins.join(inactive, "user_id", "left_anti") daily_unique = active_logins.groupBy(to_date("login_ts").alias("date")).agg(countDistinct("user_id").alias("unique_users")) ``` **Why left_anti**: Excludes rows that match....
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