sql - what is the meaning of underlying table in VIEW'S definition -

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am not understand ,

what meaning of underlying table in view definition ,

a view created joining 1 or more tables. when update record(s) in view, updates records in underlying tables make view.  so, yes, can update data in view providing have proper privileges underlying tables.

think of view stored query, appears user regular table. in practical terms, there's little difference between view:

select somefield, otherfield theview

and what's happening @ database level:

select somefield, otherfield (    select lots, of, useless,fields, somefield, otherfield    underlying, tables    join ... ) theview

views save having write sub-query each time, they're time saver in regard. however, views have downside depending on underlying query, might not able run update/delete queries against view if directly accessing underlying tables.


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