Public task directory

Technical interview practice tasks

Every entry below is a crawlable link to a unique public task page. This directory complements the interactive filters and keeps the complete catalog connected through standard pagination.

Page 357 of 386 · 18,491 tasks

SQL Case · Hard · 45 min

Marketplace operations: Group consecutive active dates into islands for each seller

Marketplace operations: Group consecutive active dates into islands for each seller.

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SQL Case · Easy · 20 min

Marketplace operations: Count distinct sellers with activity on each day

Marketplace operations: Count distinct sellers with activity on each day.

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SQL Case · Medium · 30 min

Marketplace operations: Calculate daily completed value and its running total

Marketplace operations: Calculate daily completed value and its running total.

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SQL Case · Hard · 45 min

Marketplace operations: Measure whether each creation-date cohort returned on the next calendar day

Marketplace operations: Measure whether each creation-date cohort returned on the next calendar day.

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SQL Case · Medium · 30 min

Marketplace operations: Keep the latest row for each external event key

Marketplace operations: Keep the latest row for each external event key.

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SQL Case · Easy · 20 min

Marketplace operations: Find sellers with no activity after the first active month's end

Marketplace operations: Find sellers with no activity after the first active month's end.

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SQL Case · Medium · 30 min

Marketplace operations: Find completed events above the same seller's completed-event average

Marketplace operations: Find completed events above the same seller's completed-event average.

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SQL Case · Easy · 20 min

Marketplace operations: Return the first order_completed timestamp for each seller that succeeded

Marketplace operations: Return the first ordercompleted timestamp for each seller that succeeded.

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SQL Case · Easy · 20 min

Marketplace operations: Find events whose listing reference does not exist

Marketplace operations: Find events whose listing reference does not exist.

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SQL Case · Easy · 20 min

Marketplace operations: Return the latest event for each seller

Marketplace operations: Return the latest event for each seller.

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SQL Case · Hard · 45 min

Marketplace operations: Return one row per seller with completed lifetime value and latest completed event

Marketplace operations: Return one row per seller with completed lifetime value and latest completed event.

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SQL Case · Easy · 20 min

Marketplace operations: Combine live and archived completed events without accidental deduplication

Marketplace operations: Combine live and archived completed events without accidental deduplication.

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SQL Case · Medium · 30 min

Marketplace operations: Compare completed value with the previous active month

Marketplace operations: Compare completed value with the previous active month.

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SQL Case · Medium · 30 min

Marketplace operations: Calculate the completed-event rate for every listing with activity

Marketplace operations: Calculate the completed-event rate for every listing with activity.

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SQL Case · Hard · 45 min

Marketplace operations: Resolve every listing to its root listing

Marketplace operations: Resolve every listing to its root listing.

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SQL Case · Medium · 30 min

Marketplace operations: Count sellers that produced listing_viewed and later produced order_completed

Marketplace operations: Count sellers that produced listingviewed and later produced ordercompleted.

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SQL Case · Medium · 30 min

Marketplace operations: Rank sellers by completed amount inside each region

Marketplace operations: Rank sellers by completed amount inside each region.

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SQL Case · Medium · 30 min

Marketplace operations: Find order_completed events that happened within seven days of the same seller's previous success

Marketplace operations: Find ordercompleted events that happened within seven days of the same seller's previous success.

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SQL Case · Hard · 45 min

Marketplace operations: Calculate the rolling average over each seller's current and previous two events

Marketplace operations: Calculate the rolling average over each seller's current and previous two events.

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SQL Case · Medium · 30 min

Marketplace operations: Measure the share of sellers in each segment that ever reached order_completed

Marketplace operations: Measure the share of sellers in each segment that ever reached ordercompleted.

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SQL Case · Medium · 30 min

Marketplace operations: Split each seller's events when inactivity exceeds 30 minutes

Marketplace operations: Split each seller's events when inactivity exceeds 30 minutes.

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SQL Case · Easy · 20 min

Marketplace operations: Produce one status summary row per seller

Marketplace operations: Produce one status summary row per seller.

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SQL Case · Medium · 30 min

Marketplace operations: Find the listing with the largest completed value in each category

Marketplace operations: Find the listing with the largest completed value in each category.

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SQL Case · Medium · 30 min

Marketplace operations: Return the two highest-value sellers in each segment

Marketplace operations: Return the two highest-value sellers in each segment.

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SQL Case · Easy · 20 min

Marketplace operations: List sellers that never produced a order_completed event

Marketplace operations: List sellers that never produced a ordercompleted event.

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SQL Case · Hard · 45 min

Media engagement: Find completed events whose amount exceeds their viewer segment's completed-event average

Media engagement: Find completed events whose amount exceeds their viewer segment's completed-event average.

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SQL Case · Medium · 30 min

Media engagement: Find viewers that reached play_completed no more than seven days after creation

Media engagement: Find viewers that reached playcompleted no more than seven days after creation.

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SQL Case · Medium · 30 min

Media engagement: Return viewer-title relationships active ten days after the first relationship began

Media engagement: Return viewer-title relationships active ten days after the first relationship began.

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SQL Case · Easy · 20 min

Media engagement: Find viewers with at least two recorded events

Media engagement: Find viewers with at least two recorded events.

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SQL Case · Hard · 45 min

Media engagement: Calculate each title category's share of all completed value

Media engagement: Calculate each title category's share of all completed value.

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SQL Case · Easy · 20 min

Media engagement: Calculate completed event value for each viewer segment

Media engagement: Calculate completed event value for each viewer segment.

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SQL Case · Hard · 45 min

Media engagement: Group consecutive active dates into islands for each viewer

Media engagement: Group consecutive active dates into islands for each viewer.

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SQL Case · Easy · 20 min

Media engagement: Count distinct viewers with activity on each day

Media engagement: Count distinct viewers with activity on each day.

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SQL Case · Medium · 30 min

Media engagement: Calculate daily completed value and its running total

Media engagement: Calculate daily completed value and its running total.

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SQL Case · Hard · 45 min

Media engagement: Measure whether each creation-date cohort returned on the next calendar day

Media engagement: Measure whether each creation-date cohort returned on the next calendar day.

View task

SQL Case · Medium · 30 min

Media engagement: Keep the latest row for each external event key

Media engagement: Keep the latest row for each external event key.

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SQL Case · Easy · 20 min

Media engagement: Find viewers with no activity after the first active month's end

Media engagement: Find viewers with no activity after the first active month's end.

View task

SQL Case · Medium · 30 min

Media engagement: Find completed events above the same viewer's completed-event average

Media engagement: Find completed events above the same viewer's completed-event average.

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SQL Case · Easy · 20 min

Media engagement: Return the first play_completed timestamp for each viewer that succeeded

Media engagement: Return the first playcompleted timestamp for each viewer that succeeded.

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SQL Case · Easy · 20 min

Media engagement: Find events whose title reference does not exist

Media engagement: Find events whose title reference does not exist.

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SQL Case · Easy · 20 min

Media engagement: Return the latest event for each viewer

Media engagement: Return the latest event for each viewer.

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SQL Case · Hard · 45 min

Media engagement: Return one row per viewer with completed lifetime value and latest completed event

Media engagement: Return one row per viewer with completed lifetime value and latest completed event.

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SQL Case · Easy · 20 min

Media engagement: Combine live and archived completed events without accidental deduplication

Media engagement: Combine live and archived completed events without accidental deduplication.

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SQL Case · Medium · 30 min

Media engagement: Compare completed value with the previous active month

Media engagement: Compare completed value with the previous active month.

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SQL Case · Medium · 30 min

Media engagement: Calculate the completed-event rate for every title with activity

Media engagement: Calculate the completed-event rate for every title with activity.

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SQL Case · Hard · 45 min

Media engagement: Resolve every title to its root title

Media engagement: Resolve every title to its root title.

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SQL Case · Medium · 30 min

Media engagement: Count viewers that produced play_started and later produced play_completed

Media engagement: Count viewers that produced playstarted and later produced playcompleted.

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SQL Case · Medium · 30 min

Media engagement: Rank viewers by completed amount inside each region

Media engagement: Rank viewers by completed amount inside each region.

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