Re: modifiability of system parameters

Use

    alter system set db_block_checking=true deferred;

the default is 'immediate'; the 'issys_modifiable' column tells you the requirement

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Dino Hsu wrote in message ...


>Dear all,

>

>I try to modify a system parameter with 'alter system', but I cannot.

>

><SQL*plus begin>

>

>SQL> select name, value, isses_modifiable, issys_modifiable,

>ismodified from v$parameter

>  2  where name like '%check%';

>

>NAME                           VALUE      ISSES ISSYS_MOD ISMODIFIED

>------------------------------ ---------- ----- --------- ----------

>db_block_checksum              FALSE      FALSE IMMEDIATE FALSE

>log_checkpoint_interval        10000      FALSE IMMEDIATE FALSE

>log_checkpoint_timeout         1800       FALSE IMMEDIATE FALSE

>log_checkpoints_to_alert       FALSE      FALSE FALSE     FALSE

>db_block_checking              FALSE      TRUE  DEFERRED  FALSE

>

>SQL> alter session set db_block_checking=false;

>

>Session altered.

>

>SQL> alter system set db_block_checking=true;

>alter system set db_block_checking=true

>                                      *

>ERROR at line 1:

>ORA-02096: specified initialization parameter is not modifiable with

>this option

>

><SQL*plus end>

>

><doc begin>

>

>ORA-02096 specified initialization parameter is not modifiable with

>this option

>

>Cause: Though the initialization parameter is modifiable, it cannot be

>modified using the specified command.

>

>Action: Check the Oracle8i Administrator's Guide for information about

>under what scope the parameter may be modified

>

><doc end>

>

>Anyone knows:

>1.why can't I modify it with 'alter system'?

>2.how can we get possible values of system parameters?

>

>Thanks,

>Dino

>