# Pipeline A reads the day's orders, groups by customer, and row-by-row INSERTs into a plain Snowflake

Canonical URL: <https://datadriven.io/problems/pipeline-a-reads-the-days-orders-groups-by-customer-and-r-456208b0>

Domain: Pipeline Design · Difficulty: medium

## Problem

Pipeline A reads the day's orders, groups by customer, and row-by-row INSERTs into a plain Snowflake daily_customer_summary. Each rerun multiplies the rows. The aggregation logic is correct; the bug lives entirely in the write semantics. Convert Pipeline A to Pipeline B by applying the section's named fix at the destination, leaving the aggregation untouched.

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