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oraclepowershelloledboledbcommandoledbdataadapter

OLEDB truncating Oracle LONG datatype to 100 characters


I think I know the solution to this but I'd like to get a second opinion.

I have a function called Get-Data that retrieves and returns a DataTable from an Oracle database. Now, due to Powershell being SUPER helpful, when only one record is returned from Oracle the function returns a DataRow instead of a DataTable.

When this happens and one of the columns is a LONG DataType, the field is truncated to 100 characters.

The Obvious Solution is to Return , $dt and modify my code to handle that. However, as I said, I wanted a second opinion.

Get-Data:

    function Get-Data
    { 
        [Cmdletbinding()]
        Param
        (
            [Parameter(Position=0,Mandatory=$True)]$Conn,
            [Parameter(Position=1,Mandatory=$True)]$sql
        )
            #Open the connection to the DB if closed
                    if($Conn.state -eq 'Closed')
            {
                $Conn.open()
            }

            #Create objects for querying the DB
            $readcmd = New-Object system.Data.OleDb.OleDbCommand($sql,$Conn) 
            $readcmd.CommandTimeout = '300' 
            $da = New-Object system.Data.OleDb.OleDbDataAdapter($readcmd) 
            $dt = New-Object system.Data.datatable 

            #Query the DB and fill the DataTabe with records

            [void]$da.fill($dt)

            return $dt
    }

Solution

  • Okay, so I found the source of the problem.

    When utilizing this sql statement to select from a table with a LONG datatype:

    Select * from [table]
    

    OLEDB returns the full contents of the LONG field from ORACLE

    When utilizing the following query instead for the same table:

    Select distinct * from [table]
    

    OLEDB returns only the first 100 characters of the LONG field