PL/SQL block running without printing any output

As you are not showing your script to us, lets work the other way around. create a table in your database

Create table Test_call_count (
count number(10)
);
insert into Test_call_count values (0);

and put the following into your script file

update  Test_call_count set count = count + 1;

After executing your code, you can check if it worked by selecting from the database.

The next step will be to use some begin end; block not returning any result sets.

Generally Ado can't process whole scripts. Using sql-server it can process batches, that are parts of a script separated by go statements. As far as I know for Oracle it can only process a single sql-statements or a begin end block.

Edit: Here is a litte PowerShell you can use to try what is possible:

if ($ora_loaded -eq $null)
{
    $ora_loaded = [System.Reflection.Assembly]::LoadWithPartialName("Oracle.DataAccess") 
}



$ConnectionString = "Data Source=YOUR_TNS;User ID=YOUR_ID;Password=YOUR_Password" 

function Execute-Query
{
    param (
        $sql
    )

        $conn = new-object Oracle.DataAccess.Client.OracleConnection 
        $conn.ConnectionString = $ConnectionString 
        $cmd = new-object Oracle.DataAccess.Client.OracleCommand($sql,$conn)
    #   $cmd.CommandTimeout=$timeout
        $ds = New-Object system.Data.DataSet
        $da = New-Object Oracle.DataAccess.Client.OracleDataAdapter($cmd)
        $nuLL = $da.fill($ds)
        $ds.tables[0]
        Write-Host ''
}

function Execute-NonQuery
{
    param (
        $sql
    )

        $conn = new-object Oracle.DataAccess.Client.OracleConnection 
        $conn.ConnectionString = $ConnectionString 
        $cmd = new-object Oracle.DataAccess.Client.OracleCommand($sql,$conn)
        $conn.open()
    #   $cmd.CommandTimeout=$timeout
        $cmd.ExecuteNonQuery()
        $conn.close()
}

Execute-Query "select * from Test_call_count;"
Execute-NonQuery "update  Test_call_count set count = count + 1"
Execute-NonQuery "begin update  Test_call_count set count = count + 1; end;"

For example you see, that the following fails ( I added a semicolon):

Execute-NonQuery "update  Test_call_count set count = count + 1;"

And this fails too:

Execute-NonQuery "begin update  Test_call_count set count = count + 1; end;
/"

In a first approximation you can think of the '/' as similar to the sql-server batch delimiter go.

It wouldn't perform as well, but to meet your requirements given your limitations, you could use a pipelined result set. Both your original procedure and your new procedure could then use the function. The original one would return the entire results, and the new procedure would wrap the function in a larger query that does the GROUP BY. In this way the core query code would not be duplicated. Here is a pipelined result set example along with two queries using it:

create or replace PACKAGE Example AUTHID Definer AS

Type tRow Is Record (
     F1 Date
   , F2 Date
   );
Type tTable Is Table of tRow;
Function PipelineResult(pDate In Date DEFAULT sysdate) Return tTable Pipelined;

END Example;
/


create or replace PACKAGE BODY Example AS

Function PipelineResult(pDate In Date DEFAULT sysdate) Return tTable Pipelined AS
   vYesterday Date := trunc(sysdate-1);
Begin
  For vRow IN (
      SELECT pDate, vYesterday FROM DUAL
      UNION ALL
      SELECT pDate, vYesterday-1 FROM DUAL
      UNION ALL
      SELECT pDate+1, vYesterday FROM DUAL
  )
  Loop
    Pipe Row(vRow);
  End Loop;
End;

END Example;
/


SELECT * FROM TABLE(Example.PipelineResult);

SELECT F1, count(*) FROM TABLE(Example.PipelineResult) GROUP BY F1;