Am I right in thinking that altering a column from varchar(n) to varchar(n+m) requires each tuple to be visited? Recent experience suggests this is the case but my reading of the docs has left me uncertain why this should be so. We are not changing the fundamental type of the column, nor are we attempting an operation that will fail due to existing data being incompatible with the new definition. Is there some fundamental reason why placing a higher limit on the length of existing data cannot be done solely by changing the system catalogs? Is this an optimisation that could be added to the TODO list? __ Marc
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