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Using SQL Window Functions
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Using SQL Window Functions

MediumSQL · PostgreSQL

Problem

Describe how you would use window functions in SQL.

Use the supplied players and purchases tables to demonstrate the answer. Calculate completed purchase spend for active players and assign ranks, including players with no completed purchases.

Output

  1. One row per active player, with player_name, total_spend, and spend_rank
  2. Ties receive the same rank, with gaps after ties
  3. Sort by total_spend descending, then player_id ascending

Schema

players
ColumnTypeDescription
player_idPKINTUnique player identifier
player_nameVARCHAR(100)Player display name
is_activeBOOLEANWhether the player is currently active
purchases
ColumnTypeDescription
purchase_idPKINTUnique purchase identifier
player_idINTPlayer associated with the purchase
amountDECIMAL(10,2)Purchase amount
statusVARCHAR(20)Purchase state
Tablesplayerspurchases
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Your question is Using SQL Window Functions. Start with the requirements and the two tables in the Question tab.

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