[SQL] protecting a field after creation

[Louis-David Mitterrand]

Hello,

Is there a way (outside of RULEs and  TRIGGERs) to make a field
read-only once it is INSERTed or assigned its default value? I'm
thinking, for example, of the "created" column that I add to most
tables, holding the row's creation timestamp.

Thanks in advance,

-- 
Louis-David Mitterrand - [EMAIL PROTECTED] - http://www.apartia.org

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