Sybase/ALTER TABLE: how to turn an existing column from non-nullable to nullable?

sybase alter-table
Anthony Kong picture Anthony Kong · Jul 6, 2011 · Viewed 17.6k times · Source

Hopefully the title has made it quite clear.

I would like to see an example of a alter table statement that can change an existing non-nullable column in a Sybase table to nullable.

Answer

Damien_The_Unbeliever picture Damien_The_Unbeliever · Jul 6, 2011

Modifying the NULL default value of a column:

If you are changing only the NULL default value of a column, you do not need to specify a column's datatype

(Switching the example from the above link):

alter table authors
modify address null

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