我在工作中使用 SQL 来收集信息，但没有什么太高级的（还）。
我需要确定库存进货和缺货的模式。
我有一张显示项目、位置、库存和日期的表格。我想看看随着时间的推移，物品/位置缺货和进货的时间是否有规律。该文件包含滚动的三周数据。如果某件商品在三周内持续进货或缺货，那么我需要了解它以进一步研究。
如果库存大于零，则项目/位置有库存。如果库存为零或负数，则项目/位置缺货。
感谢您的任何帮助。
样本数据
Item, location, inventory, date
1243, 10, 2, 3/12/2012
1243, 10, 0, 3/13/2012
1243, 10, -2, 3/14/2012
1243, 10, -2, 3/15/2012
1243, 10, 4, 3/16/2012
然后附加项目、位置、库存、日期记录。
接受输出建议。我只需要查看商品/位置，以及在三周的数据中它在库存和缺货之间切换的次数。
像这样的东西可能是你正在寻找的东西。这将计算每个组合从“有货”到“缺货”的次数，item反之亦然location。请注意，每个itemand的第一行location不能算作转换，因为我们不知道给定此逻辑的先前状态。
SELECT item,
location,
SUM( CASE WHEN status = 'In Stock' AND prior_status = 'Out of Stock'
THEN 1
ELSE 0
END) moved_to_out_of_stock,
SUM( CASE WHEN status = 'Out of Stock' AND prior_status = 'In Stock'
THEN 1
ELSE 0
END) moved_to_in_stock
FROM (SELECT item,
location,
status,
lag( status ) over (partition by item, location
order by dt) prior_status
FROM (SELECT item,
location,
(case when inventory <= 0
then 'Out of Stock'
else 'In Stock'
end) status,
dt
FROM your_table))
GROUP BY item, location
这表明在您发布的示例数据中，该项目一次从缺货变为有货，并从有货变为缺货一次。
SQL> ed
Wrote file afiedt.buf
1 with your_table as (
2 select 1243 item, 10 location, 2 inventory, date '2012-03-12' dt from dual union all
3 select 1243, 10, 0, date '2012-03-13' from dual union all
4 select 1243, 10, -2, date '2012-03-14' from dual union all
5 select 1243, 10, -2, date '2012-03-15' from dual union all
6 select 1243, 10, 4, date '2012-03-16' from dual
7 )
8 SELECT item,
9 location,
10 SUM( CASE WHEN status = 'In Stock' AND prior_status = 'Out of Stock'
11 THEN 1
12 ELSE 0
13 END) moved_to_out_of_stock,
14 SUM( CASE WHEN status = 'Out of Stock' AND prior_status = 'In Stock'
15 THEN 1
16 ELSE 0
17 END) moved_to_in_stock
18 FROM (SELECT item,
19 location,
20 status,
21 lag( status ) over (partition by item, location
22 order by dt) prior_status
23 FROM (SELECT item,
24 location,
25 (case when inventory <= 0
26 then 'Out of Stock'
27 else 'In Stock'
28 end) status,
29 dt
30 FROM your_table))
31* GROUP BY item, location
SQL> /
ITEM LOCATION MOVED_TO_OUT_OF_STOCK MOVED_TO_IN_STOCK
---------- ---------- --------------------- -----------------
1243 10 1 1
SELECT Item
,location
,SUM(CASE WHEN inventory>0 THEN 1 END) AS INSTOCK
,SUM(CASE WHEN inventory<=0 THEN 1 END) AS OUTSTOCK
FROM TABLE
GROUP BY Item,location;