Release 8.0
A58243-01
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Version 8 supports new INIT.ORA initialization parameters, while some release 7.3 parameters have been changed or have become obsolete in version 8.
The following topics are covered in this appendix:
The COMPATIBLE parameter specifies the release with which the Oracle server must maintain compatibility. The COMPATIBLE parameter setting in your INIT.ORA file determines the functionality of your Oracle server; therefore, it is important to set it correctly.
However, you should set the COMPATIBLE parameter at a specific point in your migration, upgrading, or downgrading process. Therefore, follow the procedure in the appropriate chapter and set the COMPATIBLE parameter only when you are instructed to do so. After the operation is complete, you can set the COMPATIBLE parameter whenever necessary.
To check your current COMPATIBLE parameter setting, issue the following command:
SVRMGR> SELECT name, value, description FROM v$parameterWHERE name="compatible";
If you are migrating or upgrading to release 8.0.4, the COMPATIBLE parameter is set to the following by default:
COMPATIBLE=8.0.0.0.0
If you do not set the COMPATIBLE parameter at all, it is set to this value. This setting has the same effect as setting COMPATIBLE to 8.0.3.0.0 and allows you to downgrade to release 8.0.3 easily, if you choose to do that in the future.
However, if you use the default setting (8.0.0.0.0), you will not be able to use the following new features of release 8.0.4:
To use these new release 8.0.4.0.0 features, set the COMPATIBLE parameter to the following:
COMPATIBLE=8.0.4.0.0
The following sections provide a brief overview of the new features that require a COMPATIBLE parameter setting of 8.0.4.0.0.
Release 8.0.4 does not support distributed object types; therefore, you cannot implement remote enqueuing or dequeuing using a standard database link. However, in release 8.0.4, you can use AQ's message propagation to enqueue to a remote queue.
For example, you can connect to database X and enqueue the message in a queue, for example "DROPBOX" located in database X. You can configure AQ so that all messages enqueued in queue "DROPBOX" are automatically propagated to another queue in database Y, regardless of whether database Y is local or remote. AQ automatically checks if the type of the remote queue in database Y is structurally equivalent to the type of the local queue in database X, and propagates the messages.
Recipients of propagated messages can be either applications or queues. If the recipient is a queue, the actual recipients are determined by the subscription list associated with the recipient queue. If the queues are remote, messages are propagated using the specified DBLINK. Only AQ to AQ message propagation is supported.
Release 8.0.4 implements an improved algorithm for System Change Number (SCN) generation. If you run Oracle Parallel Server with the INIT.ORA parameter MAX_COMMIT_PROPAGATION_DELAY set to less than 7 seconds, Oracle Corporation strongly recommends that you set COMPATIBLE to 8.0.4.0.0.
O7_DICTIONARY_ACCESSIBILITY is the INIT.ORA parameter switch that continues version 7 data dictionary behavior. It is only a temporary expedient and is not planned for future version 8 releases.
Version 8 systems typically consume more DML locks while performing DDL operations than are required for version 7 systems. Nevertheless, the version 7 DML_LOCKS parameter default settings usually are adequate for version 8 systems, even for DML-intensive applications.
The default value of DML_LOCKS is a multiple of the number of transactions, which is calculated from the number of rollback segments. However, in version 8 fewer transactions are used per rollback segment than are used in version 7. Consequently, DML_LOCKS has a lower default value in version 8. Under some extreme test conditions, a version 8 system exceeded its (version 7) DML lock limit, and the DML_LOCKS parameter value had to be increased.
Also, you may need to adjust the TRANSACTION_PER_ROLLBACK_SEGMENT parameter setting, depending on the platform-specific settings. An informational message about this change may be displayed during database startup operations, for example at Step 12 in "Migration Steps in the Version 8 Environment" on page 3-15.
You should set NLS_LANG to your environment, as follows:
Verify that the client side has the correct NLS character set environment variables. An error is generated when Oracle 7.3 NLS code tries to load a version 8 character set.
The following initialization parameters have been renamed in version 8:
The following parameters are obsolete in version 8:
CCF_IO_SIZE
CHECKPOINT_PROCESS
GC_DB_LOCKS
GC_FREELIST_GROUPS
GC_ROLLBACK_SEGMENTS
GC_SAVE_ROLLBACK_LOCKS
GC_SEGMENTS
GC_TABLESPACES
IO_TIMEOUT
INIT_SQL_FILES
IPQ_ADDRESS
IPQ_NET
LM_DOMAINS
LM_NON_FAULT_TOLERANT
OPTIMIZER_PARALLEL_PASS
PARALLEL_DEFAUILT_MAX_SCANS
PARALLEL_DEFAULT_SCAN_SIZE
SEQUENCE_CACHE_HASH_BUCKETS
SERIALIZABLE
SESSION_CACHED_CURSORS
UNLIMITED_ROLLBACK_SEGMENTS
USE_IPQ
USE_READV
USE_SIGIO
V733PLANS_ENABLED
Use the REPLICATION_DEPENDENCY_TRACKING parameter for turning DSCN tracking on or off.
TRUE, the default value, turns dependency tracking ON for read/write operations to the database. Dependency tracking is essential for the Replication Server to propagate changes in parallel.
FALSE turns dependency tracking OFF. This condition allows read/write operations to the database to run faster, but it does not produce dependency information for the Replication Server to perform parallel propagations.
This section identifies features associated with INIT.ORA file parameters from previous Oracle versions/releases that are obsolete in version 8. Oracle support for these items will likely be dropped in future releases; therefore, they should be considered desupported in version 8.
The INIT.ORA file parameter SERIALIZABLE=TRUE or _SERIALIZABLE implies automatic table-level locking ON READ in version 8. It should not be used in any version 8 installation and will probably be permanently deleted from the maintenance release after 8.1.
