In continuation to my previous posts on SQL Server Export/Import excel using R script -Part 1 &Part 2, where we saw about exporting to Excel. In this post, let us see how to import Excel into SQL Server table using R script.
In part 2 post, I have exported few tables under "Sales" schema from "WideWorldImporters" sample database into single excel file with six sheets:
Sheet 1 - CustomerTransactions
Sheet 2 - InvoiceLines
Sheet 3 - Invoices
Sheet 4 - OrderLines
Sheet 5 - Orders
Sheet 6 - SpecialDeals
While importing we have two scenarios 1) Excel file structure is defined & known
2) Excel file structure is unknown and table has to be created dynamically
Let us see example for both scenarios:
Scenario 1: Excel file structure is defined & known
For this scenario, let us try to import sheet 1 by setting the argument sheetName = 1 in read.xlsx2 function. As we know the file structure, table has been created beforehand.
SET NOCOUNT ON
DROP TABLE IF EXISTS CustomerTransactions_Import
--As we know the Excel file structure beforehand, creating an empty table to import the data from Excel sheet
SELECT NULL AS RowId,*
INTO CustomerTransactions_Import
FROM [Sales].[CustomerTransactions]WHERE 1 = 2
DECLARE @RScript NVARCHAR(MAX) =N'
Sys.setenv(JAVA_HOME="C:/Program Files/Java/jdk-11.0.1/")
require(rJava);
require("xlsx");
OutputDataSet <- read.xlsx2("H:/Temp/Blog/ImportExportExcel/Sales.xlsx", sheetName = 1,header=TRUE)
--Inserting from Excel
INSERT dbo.CustomerTransactions_Import
EXEC sp_execute_external_script
@language = N'R'
,@script = @RScript
--SELECT * FROM CustomerTransactions_Import
--Below query compares the data in source table and data imported from Excel
SELECT Src.CustomerTransactionID,Imp.CustomerTransactionID
FROM [Sales].[CustomerTransactions] SrcLEFT JOIN CustomerTransactions_Import Imp
ON Src.CustomerTransactionID = Imp.CustomerTransactionID
Scenario 2: Excel file structure is unknown and table has to be created dynamically
For this scenario, let us try to import sheet 2 by setting the argument sheetName = 2 in read.xlsx2 function. As we don't know the file structure, table will be built dynamically using
RevoScaleR function - rxDataStep and imported with data from read.xlsx2 function.
DECLARE @RScript NVARCHAR(MAX) =N'
Sys.setenv(JAVA_HOME="C:/Program Files/Java/jdk-11.0.1/")
require(rJava);
require("xlsx");
Output <- read.xlsx2("H:/Temp/Blog/ImportExportExcel/Sales.xlsx", sheetName = 2,header=TRUE)
sqlConnString <- "Driver=SQL Server;Server=''LAPTOP-LCUB6HBB''; Database=WideWorldImporters;Uid=sa;Pwd=***"
sqlTable <- "InvoiceLines_Import"
if (rxSqlServerTableExists(sqlTable, connectionString = sqlConnString)) rxSqlServerDropTable(sqlTable, connectionString = sqlConnString)
sqlDS <- RxSqlServerData(connectionString = sqlConnString,table = sqlTable)
rxDataStep(inData = Output, outFile = sqlDS,overwrite = TRUE)'
EXEC sp_execute_external_script
@language = N'R'
,@script = @RScript
sqlConnString variable needs to be set with ServerName, DatabaseName, Username & Password for ODBC SQL Server connection.
sqlTable variable is set with the name of table to be created.
More information on this topic, to be continued in part 4 ...
See Also: