OutputParameter：SQL 存储过程的输出参数：类生成器

OutputParameter：生成一个 OutputParameter 对象，该对象捕获要嵌入 SQL Server 存储过程的函数的输出参数的相关信息。 这些参数将成为存储过程的输出参数。 支持的输出参数的 R 类型为 POSIXct、数字、字符、整数、逻辑和原始参数。 如果 R 函数返回列表的非数据帧成员的命名列表，则必须创建此对象

用法

  OutputParameter(name, type)

参数

name

字符串，输出参数对象的名称。

type

输出参数对象的 R 类型。

价值

OutputParameter 对象

例子

 ## Not run:

 # See ?StoredProcedure for creating the "cleandata" table.

 # train 2 takes a data frame with clean data and outputs a model
 # as well as the data on the basis of which the model was built
 train2 <- function(in_df) {
 in_df[,"DayOfWeek"] <- factor(in_df[,"DayOfWeek"], levels=c("Monday","Tuesday","Wednesday","Thursday","Friday","Saturday","Sunday"))
   # The model formula
   formula <- ArrDelay ~ CRSDepTime + DayOfWeek + CRSDepHour:DayOfWeek
   # Train the model
   rxSetComputeContext("local")
   mm <- rxLinMod(formula, data=in_df, transformFunc=NULL, transformVars=NULL)
   mm <- rxSerializeModel(mm)
   return(list(mm = mm, in_df = in_df))
 }
 # create InputData Object for an input parameter that is a data frame
 # note: if the input parameter is not a data frame use InputParameter object
 id <- InputData(name = "in_df",
                 defaultQuery = paste0("select top 10000 ArrDelay,CRSDepTime,",
                                       "DayOfWeek,CRSDepHour from cleanData"))
 out1 <- OutputData("in_df")
 # create an OutputParameter object for the variable "mm" inside the return list
 out2 <- OutputParameter("mm", "raw")
 # connections string
 conStr <- paste0("Driver={ODBC Driver 13 for SQL Server};Server=.;Database=RevoTestDB;",
                  "Trusted_Connection=Yes;")
 # create the stored procedure object
 sp_df_op <- StoredProcedure(train2, "spTest2", id, out1, out2,
                         filePath = ".")
 registerStoredProcedure(sp_df_op, conStr)
 result <- executeStoredProcedure(sp_df_op, connectionString = conStr)
 # Get back the linear model.
 mm <- rxUnserializeModel(result$params$op1)
## End(Not run)