OutputData: Output Data for SQL Stored Procedure: Class Generator

Article
02/28/2023

OutputData: generates an OutputData Object that captures the information about the data frame that needs to be returned after the execution of the R function embedded into the stored procedure. This object must be created if the R function is returning a named list, where one of the items in the list is a data frame. The return list can contain at most one data frame.

Usage

  OutputData(name)

Arguments

`name`

A character string, the name of the data frame variable.

Value

OutputData Object

Examples


 ## 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)

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