|| at Jan 26, 2009 at 11:31 pm
If you are adding a column at the end of the table, you should be ok with the old data staying in the state that it was provided it is created with MetadataTypedColumnSetSerDe (I am not sure what happens with DynamicSerDe). MetadataTypedColumnSetSerdDe interprets missing columns at the end as nulls in the old data. Note this only works when adding columns at the end without changing names...
From: Josh Ferguson
Sent: Monday, January 26, 2009 3:06 PM
Subject: Migration Strategy
What's the current strategy for when you have a production system and you realize you need to add another column to the table or do some other thing? Seems like you'd have to make a new table, run a script to transform and load all your old data to the new table, and then remove the old table. Is this what is currently being done?