OutputData: Output Data for SQL Stored Procedure: Class Generator
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 InpuData 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)