For a small automation project I have to extract data from a table/
tables and append it to the existing excel file and feed that excel
file to a command that will load data into some other environment. I
am totally new to this. So to get started I wanted to know,
1) How to extract data from sample table Foo which has columns A,B,C
and append these values as new columns to an existing excel say
2) Can I achieve this in pl/sql script or do I need to write unix or
perl script or some other programing language, please advise?
The "extract data from a table" part is easy, you could do that with VB/ADO, or .NET/ODP.NET. It's then a matter of taking that data and appending it to a spreadsheet that might be the hard part, and how you'd do that exactly is really more of a Microsoft question than an Oracle one.
If you want to be able to do this from the database itself and your database is on Windows, you could use either [.NET Stored Procedures|http://www.oracle.com/technology/tech/dotnet/ode/index.html] if you can manipulate the spreadsheet in .net code, or you could also use Oracle's [COM Automation Feature|http://www.oracle.com/technology/tech/windows/com_auto/index.html] if you're handy with the COM object model for Excel.
How you'd do that exactly via either .net or com or vb is the crux of the problem and is something you'd need to know before it turns into an Oracle question, but if you already know how to do that and now just need to figure out a way to do that from Oracle, either of the above might help.
Hope it helps,