[possibly] dumb question

Hello colleagues,

sorry for dumb question, but can anybody advise me what default statement
should I write to fill timestamp column in record to the time of
insertion. 'now'::timestamp leads to timestamp of database creation for
all records, 'current' can not be converted to timestamp...

also, I'm rather new to triggers, can anybody help me how should look the
trigger for tracking last modification time of the record (yes, I do know
I can simply put 'now' in update statement, but I want to disable ability
to change such column by hand)

Thanks in advance.

Sincerely,
D.Marck [DM5020, DM268-RIPE, DM3-RIPN]
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*** Dmitry Morozovsky --- D.Marck --- Wild Woozle --- marck(at)rinet(dot)ru ***
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