Database Reference
In-Depth Information
Table 9-4.
Columns of X$KSPPCV
X$ Table Column
GV$ View Column
X$KSPPCV.KSPPSTDF
GV$PARAMETER.ISDEFAULT
X$KSPPCV.KSPPSTVF
GV$PARAMETER.ISMODIFIED
X$KSPPCV.KSPPSTCMNT
GV$PARAMETER.UPDATE_COMMENT
To retrieve undocumented parameters, we need to modify the where-clause in such a way
that only underscore parameters satisfy the predicates. We substitute
LIKE
ESCAPE
in place of
the awkward
TRANSLATE
used in the original GV$ view definition (file
hidden_parameters.sql
).
SELECT ksppinm name,
ksppstvl value,
ksppdesc description
FROM x$ksppi x, x$ksppcv y
WHERE (x.indx = y.indx)
AND x.inst_id=userenv('instance')
AND x.inst_id=y.inst_id
AND ksppinm LIKE '\_%' ESCAPE '\'
ORDER BY name;
Running this query on Oracle10
g
Release 2 retrieves an impressive amount of 1124 undoc-
umented parameters (540 in Oracle9
i
Release 2 and 1627 in Oracle11
g
). A small excerpt of the
query result, which includes the double underscore parameters introduced in Oracle10
g
, follows:
NAME VALUE DESCRIPTION
------------------------- ------------ -------------------------------------
_4031_dump_bitvec 67194879 bitvec to specify dumps prior to 4031
error
…
_PX_use_large_pool FALSE Use Large Pool as source of PX buffers
__db_cache_size 473956352 Actual size of DEFAULT buffer pool for
standard block size buffers
__dg_broker_service_names orcl_XPT service names for broker use
__java_pool_size 4194304 Actual size in bytes of java pool
__large_pool_size 4194304 Actual size in bytes of large pool
__shared_pool_size 117440512 Actual size in bytes of shared pool
__streams_pool_size 4194304 Actual size in bytes of streams pool
_abort_recovery_on_join FALSE if TRUE, abort recovery on join
reconfigurations
…
_yield_check_interval 100000 interval to check whether actses
should yield
1124 rows selected.
