runtimetask ROW_NUMBER · medium
First and latest order per customer
For identified customers, return customer_id, first_invoice (invoice_no of the earliest sale order), latest_invoice (invoice_no of the latest sale order) and sale_orders. Break timestamp ties by order_id.
what to return
- Columns
customer_idfirst_invoicelatest_invoicesale_ordersin this order- Rows
- 841 rows · any order
- Skill
- Pick the first and last row per group. Refresher: Latest row per group →
expected result
Your query should return exactly these columns and values. Run it and compare.
expected result841 rows · any order
| customer_id | first_invoice | latest_invoice | sale_orders |
|---|---|---|---|
| 12347 | 529924 | 581180 | 8 |
| 12353 | 529304 | 553900 | 2 |
| 12359 | 490382 | 571034 | 10 |
first 3 of 841 rows
data you can query
Retail dataset: the first 6 rows of each table. Under each column name: the kind of value it holds, and which table it links to. Your queries run on all rows.
orders6 columns · 6,722 rows
| order_idnumber · unique id | invoice_notext | customer_idnumber · links to customers | ordered_atdate & time | countrytext | order_typetext |
|---|---|---|---|---|---|
| 1 | 489438 | 18102 | 2009-12-01 09:24:00 | United Kingdom | sale |
| 2 | 489517 | 16329 | 2009-12-01 11:34:00 | United Kingdom | sale |
| 3 | C489528 | 16714 | 2009-12-01 11:50:00 | United Kingdom | cancellation |
| 4 | 489529 | 17984 | 2009-12-01 11:51:00 | United Kingdom | sale |
| 5 | 489532 | 13394 | 2009-12-01 11:58:00 | United Kingdom | sale |
| 6 | 489540 | 12913 | 2009-12-01 12:18:00 | United Kingdom | sale |
- order_idnumber · unique id
- 1
- invoice_notext
- 489438
- customer_idnumber · links to customers
- 18102
- ordered_atdate & time
- 2009-12-01 09:24:00
- countrytext
- United Kingdom
- order_typetext
- sale
- order_idnumber · unique id
- 2
- invoice_notext
- 489517
- customer_idnumber · links to customers
- 16329
- ordered_atdate & time
- 2009-12-01 11:34:00
- countrytext
- United Kingdom
- order_typetext
- sale
- order_idnumber · unique id
- 3
- invoice_notext
- C489528
- customer_idnumber · links to customers
- 16714
- ordered_atdate & time
- 2009-12-01 11:50:00
- countrytext
- United Kingdom
- order_typetext
- cancellation
- order_idnumber · unique id
- 4
- invoice_notext
- 489529
- customer_idnumber · links to customers
- 17984
- ordered_atdate & time
- 2009-12-01 11:51:00
- countrytext
- United Kingdom
- order_typetext
- sale
- order_idnumber · unique id
- 5
- invoice_notext
- 489532
- customer_idnumber · links to customers
- 13394
- ordered_atdate & time
- 2009-12-01 11:58:00
- countrytext
- United Kingdom
- order_typetext
- sale
- order_idnumber · unique id
- 6
- invoice_notext
- 489540
- customer_idnumber · links to customers
- 12913
- ordered_atdate & time
- 2009-12-01 12:18:00
- countrytext
- United Kingdom
- order_typetext
- sale
first 6 of 6,722 rows · your queries use all of them
solution.sql
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