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SQL Performance by Team and Month
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SQL Performance by Team and Month

MediumSQL · PostgreSQL

Problem

Write a SQL query to analyze operational performance by team and month, joining transaction data to team dimensions and calculating monthly totals and trends.

Use only transactions whose status is posted. Exclude transactions without a matching team dimension row.

Output

  1. One row per team and month with posted transactions.
  2. Columns: team_id, team_name, month_start, transaction_count, monthly_total, prior_month_total, total_change, and percent_change.
  3. Sort by team_id, then month_start ascending. Return NULL trend values when no prior total exists or the prior total is zero.

Schema

teams
ColumnTypeDescription
team_idPKINTUnique team identifier
team_nameVARCHAR(100)Operational team name
departmentVARCHAR(100)Department containing the team
regionVARCHAR(50)Operating region
transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
team_idINTTeam associated with the transaction
transaction_dateDATEDate the transaction was recorded
amountNUMERIC(12,2)Transaction amount
statusVARCHAR(20)Transaction processing status
Tablestransactionsteams
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