I have a flat file which contains 127 columns.
In the OLE DB Destination Editor - is there a way to select all columns and drag them across or can you only drag 1 column at a time? And does the fact that they didn't automatically map across indicate I have another problem?
if you create a file with the correct format and headers, then it will bring them all in and use the column names. The data types will default to string (50), but at least all the columns will be there
If the column names specified for the flat file source do not match the column names in the table - SSIS will not map them for you.
You don't have to drag/drop...in the lower pane you can select the drop-down and find the list of columns. On the right hand side will be the columns from the table - on the left will be the source (if mapped). When you map a column on the left it is removed from the drop-down.
You can normally just tab into the next column, hit the down-arrow key and select the column you want to map.