递归Oracle查询以计算彼此依赖的两个值

Question

我有这个表与材料库存数据：

Date(MM/DD) |received_qty| returned_qty | used_qty
01/01       |   5000     |    0         |  3500
01/02       |    0       |    0         |  1500
01/03       |   7500     |    0         |  1250
01/04       |    0       |    0         |    0

我需要再添加两列来计算“起始数量”和“每日库存”，假设如下：

• “起始数量”在第一天为零，之后是前一天的“每日库存”。
• “每日股票”是“开始数量”+ received_qty - returned_qty - used_qty

如您所见，每个值都相互依赖......

因此，添加这两列后，数据会是这样的：

Date(MM/DD) |Start_qty  |received_qty| returned_qty | used_qty | daily_stock
01/01       |    0      |   5000     |    0         |  3500    |   1500
01/02       |   1500    |    0       |    0         |  1500    |    0
01/03       |     0     |   7500     |    0         |  1250    |   6250
01/04       |   6250    |    0       |    0         |    0     |   6250

我确信这些列可以使用Oracle中存在的start with和connect by子句的递归查询生成，但我很难用脚本...

Answer 1

试试这个查询

Select t.*,
     Coalesce( 
       Sum( "received_qty" - "returned_qty" - "used_qty" )
       Over ( order by "Date" ) ,
       0) as daily_stock,
     Coalesce(
       Sum( "received_qty" - "returned_qty" - "used_qty" )
       Over ( order by "Date" 
              Rows between unbounded preceding
              And 1 preceding ), 
       0) as start_quantity

from table1 t

但是z zxswい

http://sqlfiddle.com/#!4/94417/13