Access Data Project Importing CSV File In VBA

Question

Every now and then I come across a problem with an old system one of my colleagues has developed. They tend to have thousands of lines of code to do a simple thing like impo

Answer 1

I have found a nifty way to import entire CSVs into access. I was tasked with importing three CSVs into three tables for a single database. This had to be done about 100 times, and each CSV would range from 200MB to 500MB. Since three table schemas were the same for each database I spent some time trying to find the best way to create a script to import all of these for me. I first used

DoCmd.TransferSpreadsheet acImport, acSpreadsheetTypeExcel9, p1, _
Application.CurrentProject.Path & "\Page1\_8_lift_base_" & dbName & ".csv",_
True, sh.Name & "!"

This worked for most cases, except occasionally upon opening the CSV a "read only" prompt would appear, and halt the imports until it was closed. Also, a 300MB CSV would take somewhere around 8 to 10 minutes. For 100 DBs, this is not acceptable.

What I ended up doing was to create my own XML import export specification.

Sub make_import_spec(filePath As String, tableName As String, pageNum As Long)
'By Ryan Griffin
Dim name_of_spec As String
name_of_spec = "imspec" & tableName
Dim xml As String
'This xml string contains the specifications the use for that table
xml = ""
xml = xml & "" & vbCrLf
xml = xml & "" & vbCrLf
xml = xml & "   " & vbCrLf
xml = xml & "      " & vbCrLf
xml = xml & "      " & vbCrLf
xml = xml & "           " & vbCrLf
xml = xml & "                    " & vbCrLf
xml = xml & "                    " & vbCrLf
xml = xml & "                    " & vbCrLf
xml = xml & "                    " & vbCrLf
xml = xml & "         " & vbCrLf
xml = xml & "     " & vbCrLf
xml = xml & ""
'By Ryan Griffin
'Now you can add the specification to the project
CurrentProject.ImportExportSpecifications.Add name_of_spec, xml
' This will run your specification and import you csv file
DoCmd.RunSavedImportExport name_of_spec
End Sub

After running the code with this setup I was able to import a 300MB file in just over a minute (~62seconds), and was able to make sure every column had the appropriate dataType and correct indexing (without an extra step). So with this method I was able to achieve some where between a 7 to 9 times speed increase, with the ease of knowing that the data will be correct.

*Note: for this function I am providing the CSV file path (which includes the name.csv), the desired tablename, and pagenum, which is the table reference. (I used this to distinguish between the tables. In the xml string, I had an if statement based on that pageNum, where if pageNum was 1; add these columns to the string).

This will work beautifully for all your CSV importing desires, so long as the csv files do not include a "." (period) in the name [besides the extension]. For this you will need to use a Scripting FileSystemObject to get the file, and change its' name to use something like an underscore rather than a period, before importing.

I know it may be a little long winded, but there are very few resources out there that are reliable and useful in this area. Took me a almost a day to whittle down the options and sort out the VBA mess. I hope this can help anybody out there who is having the same trouble that I was.