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SQL for Operational Trend Analysis
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SQL for Operational Trend Analysis

MediumSQL · PostgreSQL

Problem

Write a SQL query to analyze operational performance by joining transactions, members, and support cases, then aggregate by month to identify trends. Use the supplied tables and include only active members and posted transactions.

Output

  1. One row per calendar month represented by either posted transactions or support cases.
  2. Return month, active_member_count, transaction_count, total_transaction_amount, avg_transaction_amount, support_case_count, and resolved_case_count.
  3. Sort chronologically by month; use zero for missing counts or totals and NULL for an unavailable transaction average.

Schema

members
ColumnTypeDescription
member_idPKINTUnique member identifier
member_nameVARCHAR(100)Member display name
membership_statusVARCHAR(20)Current membership status
transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
member_idINTMember associated with the transaction
transaction_dateDATEDate the transaction was recorded
amountNUMERIC(12,2)Transaction amount
transaction_statusVARCHAR(20)Processing status of the transaction
support_cases
ColumnTypeDescription
case_idPKINTUnique support case identifier
member_idINTMember who opened the case
opened_atDATEDate the case was opened
resolved_atDATEDate the case was resolved
case_statusVARCHAR(20)Current support case status
Tablestransactionsmemberssupport_cases
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