`

dbConnection <- "Driver={SQL Server};Server=.;Database=****;Uid=******;Pwd=****;DBMSencoding=utf-8"
con <- odbcDriverConnect(connection = dbConnection)
Orders <- sqlQuery(con, "SELECT 
                   DOC.ID AS [Transaction]
                   ,CASE
                   WHEN DOCD.ServiceItemID IS NOT NULL 
                   THEN dbo.RemoveNumericCharacters(CONVERT(NVARCHAR (MAX),SRI.Description))
                   WHEN DOCD.StockItemID IS NOT NULL 
                   THEN dbo.RemoveNumericCharacters(CONVERT(NVARCHAR (MAX),STI.Description))  
                   END AS Item
                   ,CASE
                   WHEN  DOCD.ServiceItemID IS NOT NULL
                   THEN 'ServiceItem'
                   WHEN DOCD.StockItemID IS NOT NULL
                   THEN 'StockItem'
                   END AS [ItemType]
                   FROM Sales.Sls_Documents DOC
                   INNER JOIN Sales.Sls_DocumentDetails DOCD
                   ON DOCD.DocumentID = DOC.ID
                   LEFT  JOIN Sales.Sls_ServiceItems SRI
                   ON SRI.ID = DOCD.ServiceItemID
                   LEFT JOIN Warehouse.StockItems STI
                   ON STI.Id = DOCD.StockItemID
                   WHERE CASE
                   WHEN DOCD.ServiceItemID IS NOT NULL 
                   THEN SRI.Description
                   WHEN DOCD.StockItemID IS NOT NULL
                   THEN STI.Description
                   END IS NOT NULL")
Orders$Item <- as.character(Orders$Item)

`

session sionInfo（）： R版本3.4.3（2017-11-30）平台：x86_64-w64-mingw32/x64（64-bit）运行于：Windows 10 x64（build 16299）

矩阵产品：默认

地区： 1LC_COLLATE=English_UnitedLC_CTYPE=English_UnitedLC_MONETARY=English_UnitedLC_NUMERIC=C[5]LC_TIME=English_United