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 352 of 386 · 18,491 tasks

SQL Case · Easy · 20 min

Developer productivity: Find events whose repository reference does not exist

Developer productivity: Find events whose repository reference does not exist.

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SQL Case · Easy · 20 min

Developer productivity: Return the latest event for each developer

Developer productivity: Return the latest event for each developer.

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SQL Case · Hard · 45 min

Developer productivity: Return one row per developer with completed lifetime value and latest completed event

Developer productivity: Return one row per developer with completed lifetime value and latest completed event.

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SQL Case · Easy · 20 min

Developer productivity: Combine live and archived completed events without accidental deduplication

Developer productivity: Combine live and archived completed events without accidental deduplication.

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SQL Case · Medium · 30 min

Developer productivity: Compare completed value with the previous active month

Developer productivity: Compare completed value with the previous active month.

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SQL Case · Medium · 30 min

Developer productivity: Calculate the completed-event rate for every repository with activity

Developer productivity: Calculate the completed-event rate for every repository with activity.

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SQL Case · Hard · 45 min

Developer productivity: Resolve every repository to its root repository

Developer productivity: Resolve every repository to its root repository.

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SQL Case · Medium · 30 min

Developer productivity: Count developers that produced build_started and later produced build_succeeded

Developer productivity: Count developers that produced buildstarted and later produced buildsucceeded.

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SQL Case · Medium · 30 min

Developer productivity: Rank developers by completed amount inside each region

Developer productivity: Rank developers by completed amount inside each region.

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SQL Case · Medium · 30 min

Developer productivity: Find build_succeeded events that happened within seven days of the same developer's previous success

Developer productivity: Find buildsucceeded events that happened within seven days of the same developer's previous success.

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SQL Case · Hard · 45 min

Developer productivity: Calculate the rolling average over each developer's current and previous two events

Developer productivity: Calculate the rolling average over each developer's current and previous two events.

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SQL Case · Medium · 30 min

Developer productivity: Measure the share of developers in each segment that ever reached build_succeeded

Developer productivity: Measure the share of developers in each segment that ever reached buildsucceeded.

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SQL Case · Medium · 30 min

Developer productivity: Split each developer's events when inactivity exceeds 30 minutes

Developer productivity: Split each developer's events when inactivity exceeds 30 minutes.

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SQL Case · Easy · 20 min

Developer productivity: Produce one status summary row per developer

Developer productivity: Produce one status summary row per developer.

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SQL Case · Medium · 30 min

Developer productivity: Find the repository with the largest completed value in each category

Developer productivity: Find the repository with the largest completed value in each category.

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SQL Case · Medium · 30 min

Developer productivity: Return the two highest-value developers in each segment

Developer productivity: Return the two highest-value developers in each segment.

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SQL Case · Easy · 20 min

Developer productivity: List developers that never produced a build_succeeded event

Developer productivity: List developers that never produced a buildsucceeded event.

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SQL Case · Hard · 45 min

Fintech ledger analytics: Find completed events whose amount exceeds their customer segment's completed-event average

Fintech ledger analytics: Find completed events whose amount exceeds their customer segment's completed-event average.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Find customers that reached transfer_settled no more than seven days after creation

Fintech ledger analytics: Find customers that reached transfersettled no more than seven days after creation.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Return customer-account_product relationships active ten days after the first relationship began

Fintech ledger analytics: Return customer-accountproduct relationships active ten days after the first relationship began.

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SQL Case · Easy · 20 min

Fintech ledger analytics: Find customers with at least two recorded events

Fintech ledger analytics: Find customers with at least two recorded events.

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SQL Case · Hard · 45 min

Fintech ledger analytics: Calculate each account_product category's share of all completed value

Fintech ledger analytics: Calculate each accountproduct category's share of all completed value.

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SQL Case · Easy · 20 min

Fintech ledger analytics: Calculate completed event value for each customer segment

Fintech ledger analytics: Calculate completed event value for each customer segment.

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SQL Case · Hard · 45 min

Fintech ledger analytics: Group consecutive active dates into islands for each customer

Fintech ledger analytics: Group consecutive active dates into islands for each customer.

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SQL Case · Easy · 20 min

Fintech ledger analytics: Count distinct customers with activity on each day

Fintech ledger analytics: Count distinct customers with activity on each day.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Calculate daily completed value and its running total

Fintech ledger analytics: Calculate daily completed value and its running total.

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SQL Case · Hard · 45 min

Fintech ledger analytics: Measure whether each creation-date cohort returned on the next calendar day

Fintech ledger analytics: Measure whether each creation-date cohort returned on the next calendar day.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Keep the latest row for each external event key

Fintech ledger analytics: Keep the latest row for each external event key.

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SQL Case · Easy · 20 min

Fintech ledger analytics: Find customers with no activity after the first active month's end

Fintech ledger analytics: Find customers with no activity after the first active month's end.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Find completed events above the same customer's completed-event average

Fintech ledger analytics: Find completed events above the same customer's completed-event average.

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SQL Case · Easy · 20 min

Fintech ledger analytics: Return the first transfer_settled timestamp for each customer that succeeded

Fintech ledger analytics: Return the first transfersettled timestamp for each customer that succeeded.

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SQL Case · Easy · 20 min

Fintech ledger analytics: Find events whose account_product reference does not exist

Fintech ledger analytics: Find events whose accountproduct reference does not exist.

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SQL Case · Easy · 20 min

Fintech ledger analytics: Return the latest event for each customer

Fintech ledger analytics: Return the latest event for each customer.

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SQL Case · Hard · 45 min

Fintech ledger analytics: Return one row per customer with completed lifetime value and latest completed event

Fintech ledger analytics: Return one row per customer with completed lifetime value and latest completed event.

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SQL Case · Easy · 20 min

Fintech ledger analytics: Combine live and archived completed events without accidental deduplication

Fintech ledger analytics: Combine live and archived completed events without accidental deduplication.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Compare completed value with the previous active month

Fintech ledger analytics: Compare completed value with the previous active month.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Calculate the completed-event rate for every account_product with activity

Fintech ledger analytics: Calculate the completed-event rate for every accountproduct with activity.

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SQL Case · Hard · 45 min

Fintech ledger analytics: Resolve every account_product to its root account_product

Fintech ledger analytics: Resolve every accountproduct to its root accountproduct.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Count customers that produced transfer_started and later produced transfer_settled

Fintech ledger analytics: Count customers that produced transferstarted and later produced transfersettled.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Rank customers by completed amount inside each region

Fintech ledger analytics: Rank customers by completed amount inside each region.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Find transfer_settled events that happened within seven days of the same customer's previous success

Fintech ledger analytics: Find transfersettled events that happened within seven days of the same customer's previous success.

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SQL Case · Hard · 45 min

Fintech ledger analytics: Calculate the rolling average over each customer's current and previous two events

Fintech ledger analytics: Calculate the rolling average over each customer's current and previous two events.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Measure the share of customers in each segment that ever reached transfer_settled

Fintech ledger analytics: Measure the share of customers in each segment that ever reached transfersettled.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Split each customer's events when inactivity exceeds 30 minutes

Fintech ledger analytics: Split each customer's events when inactivity exceeds 30 minutes.

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SQL Case · Easy · 20 min

Fintech ledger analytics: Produce one status summary row per customer

Fintech ledger analytics: Produce one status summary row per customer.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Find the account_product with the largest completed value in each category

Fintech ledger analytics: Find the accountproduct with the largest completed value in each category.

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SQL Case · Medium · 30 min

Fintech ledger analytics: Return the two highest-value customers in each segment

Fintech ledger analytics: Return the two highest-value customers in each segment.

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SQL Case · Easy · 20 min

Fintech ledger analytics: List customers that never produced a transfer_settled event

Fintech ledger analytics: List customers that never produced a transfersettled event.

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