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Convert MySQL to NoSQL
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Convert MySQL to NoSQL

HardSQL · PostgreSQL

Problem

Explain how you would convert given MySQL code into equivalent NoSQL code.

Use the supplied relational structure and data to demonstrate how the logic would be represented in a document-oriented system. Preserve filtering, monthly aggregation, previous-period comparison, ranking, null handling, and ordering.

Output

  1. Return one row per account and month with month, region_name, account_id, account_name, settled_amount, previous_month_amount, change_amount, and region_rank.
  2. Include only settled activity from January through March 2025, ordered by month, region_name, and region_rank.

Schema

accounts
ColumnTypeDescription
account_idPKINTUnique account identifier
account_nameVARCHAR(100)Account display name
region_idINTAccount region identifier
regions
ColumnTypeDescription
region_idPKINTUnique region identifier
region_nameVARCHAR(80)Region name
transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
account_idINTAccount associated with the transaction
posted_atTIMESTAMPTransaction posting timestamp
amountNUMERIC(12,2)Transaction amount
statusVARCHAR(20)Transaction processing status
Tablesaccountsregionstransactions
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