| # Task: 014 |
|
|
| **Database:** retails |
|
|
| ## Question |
| Show the supplier that supplies the most parts in their inventory in each region. |
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|
| ## Gold Query |
|
|
| ```sql |
| WITH supplier_part_count AS ( |
| SELECT r.r_regionkey AS region_key, |
| r.r_name AS region_name, |
| s.s_suppkey, |
| s.s_name, |
| COUNT(DISTINCT ps.ps_partkey) AS total_quantity, |
| RANK() OVER (PARTITION BY r.r_regionkey ORDER BY COUNT(DISTINCT ps.ps_partkey) DESC) AS rn |
| FROM supplier s |
| JOIN nation n ON s.s_nationkey = n.n_nationkey |
| JOIN region r ON n.n_regionkey = r.r_regionkey |
| JOIN partsupp ps ON s.s_suppkey = ps.ps_suppkey |
| GROUP BY r.r_regionkey, r.r_name, s.s_suppkey, s.s_name |
| ) |
| SELECT region_key, region_name, s_suppkey, s_name, total_quantity |
| FROM supplier_part_count |
| WHERE rn = 1; |
| ``` |
|
|
| **Execution Result:** |
|
|
| | region_key | region_name | s_suppkey | s_name | total_quantity | |
| |--------------|---------------|-------------|--------------------|------------------| |
| | 0 | AFRICA | 2 | Supplier#000000002 | 80 | |
| | 0 | AFRICA | 7 | Supplier#000000007 | 80 | |
| | 0 | AFRICA | 8 | Supplier#000000008 | 80 | |
| | 0 | AFRICA | 21 | Supplier#000000021 | 80 | |
| | 0 | AFRICA | 22 | Supplier#000000022 | 80 | |
| | 0 | AFRICA | 23 | Supplier#000000023 | 80 | |
| | 0 | AFRICA | 30 | Supplier#000000030 | 80 | |
| | 0 | AFRICA | 37 | Supplier#000000037 | 80 | |
| | 0 | AFRICA | 39 | Supplier#000000039 | 80 | |
| | 0 | AFRICA | 41 | Supplier#000000041 | 80 | |
| | ... | ... | ... | ... | ... | |
| | 4 | MIDDLE EAST | 9965 | Supplier#000009965 | 80 | |
| | 4 | MIDDLE EAST | 9966 | Supplier#000009966 | 80 | |
| | 4 | MIDDLE EAST | 9967 | Supplier#000009967 | 80 | |
| | 4 | MIDDLE EAST | 9969 | Supplier#000009969 | 80 | |
| | 4 | MIDDLE EAST | 9985 | Supplier#000009985 | 80 | |
| | 4 | MIDDLE EAST | 9989 | Supplier#000009989 | 80 | |
| | 4 | MIDDLE EAST | 9991 | Supplier#000009991 | 80 | |
| | 4 | MIDDLE EAST | 9992 | Supplier#000009992 | 80 | |
| | 4 | MIDDLE EAST | 9994 | Supplier#000009994 | 80 | |
| | 4 | MIDDLE EAST | 9996 | Supplier#000009996 | 80 | |
| |
| *... truncated (10000 rows total)* |
