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SQL Basics for Data Work
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SQL Basics for Data Work

EasySQL · PostgreSQL

Problem

Tell me about a time you used SQL to answer a simple data question and validated the result.

For this exercise, use the supplied orders table to count orders for each non-null status and describe how you would independently validate the result.

Output

  1. One row per non-null order_status, with columns order_status and order_count.
  2. Exclude orders whose status is NULL.
  3. Order by order_count descending, then order_status ascending for ties.

Schema

orders
ColumnTypeDescription
order_idPKINTUnique order identifier
order_statusVARCHAR(30)Current order status
order_totalNUMERIC(10,2)Total value of the order
Tablesorders
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Your question is SQL Basics for Data Work. Start with the requirements and the one table in the Question tab.

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CodePostgreSQL
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