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SQL for Financial Data Validation
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SQL for Financial Data Validation

MediumSQL · PostgreSQL

Problem

Write a SQL query to analyze financial data and validate assumptions in a real scenario at T-Mobile. Compare posted transaction totals with monthly assumptions, treating missing actual totals as zero. Use the financial_transactions, accounts, and monthly_assumptions tables.

Output

  1. One row per assumption period and account type.
  2. Columns: account_type, period_start, actual_amount, assumed_amount, variance, variance_pct, and validation_status.
  3. Include every assumption, order by account_type and period_start, and report Match only when actual and assumed amounts are equal.

Schema

financial_transactions
ColumnTypeDescription
transaction_idPKINTUnique financial transaction identifier
account_idINTAccount associated with the transaction
transaction_dateDATEDate the transaction was recorded
amountNUMERIC(12,2)Transaction amount
statusVARCHAR(20)Transaction processing status
accounts
ColumnTypeDescription
account_idPKINTUnique account identifier
account_typeVARCHAR(30)Financial account classification
monthly_assumptions
ColumnTypeDescription
assumption_idPKINTUnique assumption identifier
account_typeVARCHAR(30)Account classification for the assumption
period_startDATEFirst day of the assumption month
assumed_amountNUMERIC(12,2)Expected amount for the account type and month
Tablesfinancial_transactionsaccountsmonthly_assumptions
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