Is there any way to force clear the cache?
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> In article <87vgezw1zd.fsf_at_altavista.net>, Martin says...
> >
> >I know how one could write a "describe" command by querying the data
> >dictionary, but recently I made a strange observation:
> >
> >I turned on sqltrace, ran a "describe" command and turned sqltrace
> >back off. The trace file showed the "trace on" and "trace off"
> >commands but the "describe" command itself literally left no trace at
> >all.
> >
> >How could sqlplus possibly implement a describe command without causing
> >an sqltrace ? Also it is amazingly fast, even when you describe a
> >table at the other end of a database link which is aliased by a
> >synonym.
> >
>
> it gets it from the dictionary cache. If you fire up an instance or
describe
> something that hasn't been described, you'll see the recursive SQL used to
get
> the info into the dictionary cache.
>
> When you DON'T see the SQL being executed -- that just means the info was
in the
> dictionary cache.
>
> >I also ran "strace sqlplus". This showed a socked write and a socked
> >read. This is no surprise, all commands basically look like like this
> >(not just describe). I believe this is just classic SQL*Net
> >communication. I don't know WHAT it writes though.
>
> --
> Thomas Kyte (tkyte@us.oracle.com) http://asktom.oracle.com/
> Expert one on one Oracle, programming techniques and solutions for Oracle.
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>
Received on Sun Dec 23 2001 - 22:19:14 CST
