我有这两个表：
+---------------+-------------+---------------------+----------+---------+
| items_ordered | | | | |
+---------------+-------------+---------------------+----------+---------+
| customerid | order_date | item | quantity | price |
| 10330 | 30-Jun-1999 | Pogo stick | 1 | 28.00 |
| 10101 | 30-Jun-1999 | Raft | 1 | 58.00 |
| 10298 | 01-Jul-1999 | Skateboard | 1 | 33.00 |
| 10101 | 01-Jul-1999 | Life Vest | 4 | 125.00 |
| 10299 | 06-Jul-1999 | Parachute | 1 | 1250.00 |
| 10339 | 27-Jul-1999 | Umbrella | 1 | 4.50 |
| 10449 | 13-Aug-1999 | Unicycle | 1 | 180.79 |
| 10439 | 14-Aug-1999 | Ski Poles | 2 | 25.50 |
| 10101 | 18-Aug-1999 | Rain Coat | 1 | 18.30 |
| 10449 | 01-Sep-1999 | Snow Shoes | 1 | 45.00 |
| 10439 | 18-Sep-1999 | Tent | 1 | 88.00 |
| 10298 | 19-Sep-1999 | Lantern | 2 | 29.00 |
| 10410 | 28-Oct-1999 | Sleeping Bag | 1 | 89.22 |
| 10438 | 01-Nov-1999 | Umbrella | 1 | 6.75 |
| 10438 | 02-Nov-1999 | Pillow | 1 | 8.50 |
| 10298 | 01-Dec-1999 | Helmet | 1 | 22.00 |
| 10449 | 15-Dec-1999 | Bicycle | 1 | 380.50 |
| 10449 | 22-Dec-1999 | Canoe | 1 | 280.00 |
| 10101 | 30-Dec-1999 | Hoola Hoop | 3 | 14.75 |
| 10330 | 01-Jan-2000 | Flashlight | 4 | 28.00 |
| 10101 | 02-Jan-2000 | Lantern | 1 | 16.00 |
| 10299 | 18-Jan-2000 | Inflatable Mattress | 1 | 38.00 |
| 10438 | 18-Jan-2000 | Tent | 1 | 79.99 |
| 10413 | 19-Jan-2000 | Lawnchair | 4 | 32.00 |
| 10410 | 30-Jan-2000 | Unicycle | 1 | 192.50 |
| 10315 | 2-Feb-2000 | Compass | 1 | 8.00 |
| 10449 | 29-Feb-2000 | Flashlight | 1 | 4.50 |
| 10101 | 08-Mar-2000 | Sleeping Bag | 2 | 88.70 |
| 10298 | 18-Mar-2000 | Pocket Knife | 1 | 22.38 |
| 10449 | 19-Mar-2000 | Canoe paddle | 2 | 40.00 |
| 10298 | 01-Apr-2000 | Ear Muffs | 1 | 12.50 |
| 10330 | 19-Apr-2000 | Shovel | 1 | 16.75 |
+ --------------- + ------------- + ---------------- ----- + ---------- + --------- +
+------------+-----------+----------+--------------+----------------+---+
| customers | | | | | |
+------------+-----------+----------+--------------+----------------+---+
| customerid | firstname | lastname | city | state | |
| 10101 | John | Gray | Lynden | Washington | |
| 10298 | Leroy | Brown | Pinetop | Arizona | |
| 10299 | Elroy | Keller | Snoqualmie | Washington | |
| 10315 | Lisa | Jones | Oshkosh | Wisconsin | |
| 10325 | Ginger | Schultz | Pocatello | Idaho | |
| 10329 | Kelly | Mendoza | Kailua | Hawaii | |
| 10330 | Shawn | Dalton | Cannon Beach | Oregon | |
| 10338 | Michael | Howell | Tillamook | Oregon | |
| 10339 | Anthony | Sanchez | Winslow | Arizona | |
| 10408 | Elroy | Cleaver | Globe | Arizona | |
| 10410 | Mary Ann | Howell | Charleston | South Carolina | |
| 10413 | Donald | Davids | Gila Bend | Arizona | |
| 10419 | Linda | Sakahara | Nogales | Arizona | |
| 10429 | Sarah | Graham | Greensboro | North Carolina | |
| 10438 | Kevin | Smith | Durango | Colorado | |
| 10439 | Conrad | Giles | Telluride | Colorado | |
| 10449 | Isabela | Moore | Yuma | Arizona | |
+------------+-----------+----------+--------------+----------------+---+
我想要做的是能够将每个州的总价格加起来。这将总结客户根据其位置花费的总价。但我无法想象你如何在SQL中做到这一点。我能够做的是通过userid多次获取状态列表以获得下表：
+-----------------+-------+---------+
| Arizona | 10339 | 4.50 |
| Arizona | 10449 | 970.79 |
| Arizona | 10298 | 147.88 |
| Arizona | 10413 | 128.00 |
| Colorado | 10439 | 139.00 |
| Colorado | 10438 | 95.24 |
| Oregon | 10330 | 156.75 |
| Sourth Carolina | 10410 | 281.72 |
| Washington | 10299 | 1288.00 |
| Washington | 10101 | 813.95 |
| Wisconsin | 10315 | 8.00 |
+-----------------+-------+---------+
> SELECT c.State, i.customerid, SUM(i.quantity * i.price)
> FROM items_ordered i, customers c
> WHERE c.customerid = i.customerid
> GROUP BY i.customerid
> ORDER BY c.State;
以下是我试图展示的表格：
+-----------------+-------+---------+
| Arizona | 10339 | 1251.17 |
| Colorado | 10438 | 234.24 |
| Oregon | 10330 | 156.75 |
| Sourth Carolina | 10410 | 281.72 |
| Washington | 10299 | 2101.95 |
| Wisconsin | 10315 | 8.00 |
+-----------------+-------+---------+
答案 0 :(得分：0)
答案 1 :(得分：0)
您希望按州加总 - 所以只需从选择列表中删除客户ID，然后按州分组：
SELECT c.State, SUM(i.quantity * i.price)
FROM items_ordered i, customers c
WHERE c.customerid = i.customerid
GROUP BY c.State