Entity Linq中兩列的總和

Question

我正在努力將查詢從sql轉換爲實體linq。我的選擇應該是prodhis.stock_units_free總和減去prodhis.stock_units_it總和

任何人都可以指向正確的方向嗎？

這是我

Dim res As Integer = (From it In rmis.product_detail Join prodhis In rmis.PRODUCT_HISTORY On it.SKU_ID Equals prodhis.SKU_ID _ 
         Where prodhis.WEEK_SELECTOR = cws AndAlso 
         it.POS_CODE = ItemID AndAlso 
         prodhis.BRANCH_ID = 23 
         'Stuck Here: 
Select (sum(prodhis.STOCK_UNITS_FREE) - sum(prodhis.STOCK_UNITS_IT)) 

和不申報錯誤....

感謝

Answer 1

更改您的選擇：

Select prodhis.STOCK_UNITS_FREE - prodhis.STOCK_UNITS_IT).Sum();