qadding the columns them selves is just a DDL operation. you would not need to do that inside SSIS.
ALTER TABLE ADD Column1 varchar(etc...
i suspect you mean what about the data that is going to go INTO the new columns.
That's where you need to explain quite a bit more.
you didn't say what the new column values would contain. can they be calculated form existing data? are they just a calculation?
can the data be re-imported with the new columns*(ie they were ignored before?)
I am just guessing here, but can you import old data to a staging table, and update the exiting data so the new columns are populated??
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