Error output question

Hello,

I realize I have a question about what constitutes an "error" for an error output.

For example, a flat file source has an error output for "bad rows", that is, when it encounters "unexpected data". What specifically is "unexpected data"? Is this documented somewhere?

Another example would be an OLE DB source that uses a query to retrieve row. This too, has an error output, but I realize I have no clue what would constitute bad data from a table. I mean, data in a table is just data, so what would constitute an error from an OLE DB source? I can't think of one thing. Where are these "rules" documented, if anywhere?

Thanks

"Handling Errors in Data" in Books Online has some great information on this.

Errors can be different for different components. Sources most often suffer from data type conversion issues. The error output adds an ErrorCode and you can call Microsoft.SqlServer.Dts.Pipeline.Wrapper.IDTSComponentMetaData90.GetErrorDescription in a script component to see the actual error message.