Splitting csv file based on column value <SOLVED>

Question

I have this large csv (semicolon separated) file that I need to split into about 300 files based on the value in second column (file has header names).The file has about + 3 million rows and headers for 54 columns I have tried using this script with Powershell but it seems not to run. I can see in task manager that memory is building for a while but there is no output at all or error messages. I find this script here Splitting a xlsx/csv file based on column value and change the script to fit my needs. Have I missed something or what is wrong with this script as no output is executed...

What is missing?

$csv = Import-Csv C:\Data\Points\Se\Test\Data191017.csv -Delimiter ';'

$names = $csv | select -ExpandProperty OFFICENAME -Unique

foreach ($name in $names) { $csv | where {$_.name -like $name} | export-csv C:\Data\Points\Se\Test\20191028_$name.csv }

Answer 1

I finally got it to work, I added -Encoding to both import and export line (not sure that is needed). Now it runs correctly with characters and all so I'm happy :)

Thanks for helping out and getting me in right directions, below is the script that works for my purposes ...

$Source = 'Data_191107.csv'
$Dest = 'C:\temp\test\'
Import-Csv $Source -Delimiter ';' -Encoding 'ISO-8859-1' | %{
$_ | Export-csv -Path "$Dest$($_.OFFICENAME).csv" -Encoding 'ISO-8859-1' -NoTypeInformation -Delimiter ';' -Append
}

Answer 2

Not an expert, but from what I've read, you want to avoid intermeidate variables, especially with large objecgts, and leverage the pipeline. The following worked with a small sample:

$Source = 'C:\Data\Points\Se\Test\Data191017.csv'
$Dest = 'C:\Data\Points\Se\Test\'

Import-Csv $Source -Delimiter ';' | %{
   $_ | Export-csv -Path "$Dest$($_.OFFICENAME).csv" -NoTypeInformation -Delimiter ';' -Append
}

Splatting the parameters makes it easier to read, but not sure of the effect on execution time for a large data set:

$Source = 'C:\Data\Points\Se\Test\Data191017.csv'
$Dest = 'C:\Data\Points\Se\Test\'

Import-Csv $Source -Delimiter ';' | %{
   $splat = @{
      'Path'              = "$Dest$($_.Country).csv"
      'Delimiter'         = ';'
      'InputObject'       = $_
      'Append'            = $True
      'NoTypeInformation' = $True
   }
   Export-csv @splat
}