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START DBE NEWLOG
The START DBE NEWLOG statement establishes a connection with a
given DBEnvironment and creates one or two new log files for that
DBEnvironment. It establishes a set of startup parameters that apply to
this and all subsequent connections until all connections to the
DBEnvironment have been terminated. Any start up parameters not
explicitly specified are taken from the DBECon file except the enabling
of audit logging. This statement reinitializes log file(s) when you need
to change the size, invoke a dual logging or startup, or alter audit
logging.
Scope
ISQL or Application Programs
SQL Syntax--START DBE NEWLOG
START DBE 'DBEnvironmentName' [AS 'ConnectionName'] [MULTI] NEWLOG
[{ARCHIVE} ]
[{DUAL } |...| LOG ]
[{AUDIT } ]
[ ]
[BUFFER = (DataBufferPages, LogBufferPages) ]
[TRANSACTION = MaxTransactions ]
[ {TimeoutValue [SECONDS]} ]
[MAXIMUM TIMEOUT = { [MINUTES]} ]
[ { } ]
[ {NONE } ]
[ ]
[ {TimeoutValue [SECONDS]} ]
[DEFAULT TIMEOUT = { [MINUTES]} ]
[ { } ]
[ {MAXIMUM } ]
[ ]
[RUN BLOCK = ControlBlockPages ] |,...| NewLogDefinition
[DEFAULT PARTITION = {DefaultPartitionNumber}]
[ {NONE }]
[ ]
[ {CommentPartitionNumber}]
[COMMENT PARTITION = {DEFAULT }]
[ {NONE }]
[ ]
[MAXPARTITIONS = MaximumNumberOfPartitions ]
[AUDIT NAME = 'AuditName' ]
[{COMMENT } ]
[{DATA } ]
[{DEFINITION } ]
[{STORAGE } |...| AUDIT ELEMENTS ]
[{AUTHORIZATION} ]
[{SECTION } ]
[{ALL } ]
Parameters--START DBE NEWLOG
DBEnvironmentName identifies the DBEnvironment in which you want to
initialize one or two new log files. Unless you
specify a group and account, ALLBASE/SQL assumes
the name is in your current group and account.
DBEnvironmentName cannot exceed 36 bytes.
You can also use an MPE/iX back reference for
DBEnvironmentName as shown in the following
example:
:FILE DBE = PartsDBE.SomeGrp.Acct
START DBE '*DBE' NEWLOG
ConnectionName associates a user specified name with this
connection. This name must be unique for each
DBEnvironment connection within an application.
If a ConnectionName is not specified,
DBEnvironmentName is the default. ConnectionName
cannot exceed 128 bytes.
MULTI indicates the DBEnvironment can be accessed after
log initialization in multiuser mode.
ARCHIVE causes ALLBASE/SQL to initialize a new log in
archive mode. If you omit this parameter, the
log starts in nonarchive mode.
DUAL causes ALLBASE/SQL to maintain two separate logs,
preferably on different media. Keeping the log
files on separate media ensures that a media
failure on one device leaves the other log
undamaged. Each log write operation is performed
on both logs. Normally, only one log is read;
but if an error is encountered, ALLBASE/SQL
switches to the other log. Data integrity is
maintained provided at least one good copy of
each log record is on at least one of the logs.
AUDIT Identifies the DBEnvironment as one that will
have audit logging performed on it with the
elements specified in the AUDIT ELEMENTS clause.
This causes ALLBASE/SQL to create audit log
records as well as normal log records in the log
file so that the database can be audited.
DataBufferPages specifies the number of 4096-byte data buffer
pages to be used. Data buffer pages hold index
and data pages.
You can request up to 50,000 data buffer pages.
The minimum number of data buffer pages is 15.
The default number is 100. The total number of
data buffer pages and runtime control block pages
cannot exceed 256 Mbytes.
LogBufferPages specifies the number of log buffer pages to be
used. You as can request from 24 to 1024 log
buffer pages, limited by the amount of storage
available. The default number of log buffer
pages is 24.
MaxTransactions specifies the maximum number of concurrent
transactions to be supported. You can specify a
value from 2 to 240.[REV BEG] The default is
50.[REV END] This value overrides the maximum
value stored in the DBECon file. Any attempt to
start a transaction beyond the maximum limit
waits for the specified TIMEOUT and returns an
error if TIMEOUT is exceeded. For each user
logged on to the system at any one time, you
should allow 2 concurrent transactions for just
being connected to the DBE.
MAXIMUM TIMEOUT specifies the maximum user timeout value. This
value temporarily overrides the maximum stored in
the DBECon file. When no value is specified, the
DBECon file value is the default.
DEFAULT TIMEOUT specifies the default user timeout value. This
value temporarily overrides the maximum stored in
the DBECon file. When no value is specified, the
DBECon file value is the default.
TimeoutValue is an integer literal greater than zero. If the
TimeoutValue is not qualified by MINUTES, SECONDS
is assumed. If representing seconds,
TimeoutValue must be in the range of 1 to
2,147,483,647. If representing minutes,
TimeoutValue must be in the range of 1 to
35,791,394.
ControlBlockPages specifies the number of runtime control blocks to
be allocated. Any value specified here
temporarily overrides the value specified in the
DBECon file.
You can specify a value from 17 to 2,000 pages
for this parameter. The default is 37 pages.
The total number of data buffer pages and runtime
control block pages cannot exceed 256 Mbytes.
DefaultPartitionNumber Specifies the default partition number for the
DBEnvironment. DefaultPartitionNumber must be in
the range 1 and 32767. If NONE is specified,
tables assigned to the DEFAULT PARTITION do not
generate audit log records. no tables in the
DBEnvironment are prepared for audit logging and
no operation done on these tables is logged. See
the CREATE TABLE and ALTER TABLE statements for
information on assigning a partition for a table.
CommentPartitionNumber Specifies the partition number for comments made
in the DBEnvironment. CommentPartitionNumber
must be a number between 1 and 32767. If no
COMMENT PARTITION is specified, DEFAULT is
implied.
If the comment partition is DEFAULT and the
default partition number is later changed in a
START DBE NEWLOG statement (but the comment
partition is not changed from DEFAULT), the
comment partition number will also change to the
new default partition number.
MaximumNumberOfPartitionspecifies the maximum number of partitions for
the DBEnvironment. MaximumNumberOfPartitions is
required to be a number between 1 and 831. This
number indicates the number of partition
instances the DBEnvironment is expected to track.
For audit logging purposes, the number of
partition instances is calculated as the sum of
the number of DATA partitions and the number of
elements (except the DATA audit element)
specified in the AUDIT ELEMENTS clause.
Specifying ALL audit elements (see below)
includes 6 elements, implying that 6 partitions
are used. Set this value only as high as needed
so that unnecessary space is not reserved unless
you plan for more partitions or audit elements.
AuditName Specifies the name of this audit DBEnvironment.
AuditName is limited to 8 bytes. This clause
must be specified if AUDIT LOG has been
specified. The AuditName appears in outputs of
the Audit Tool.
AUDIT ELEMENTS Specifies the types of audit logging that will be
done for the database. If this clause is omitted
and AUDIT LOG is specified, DATA AUDIT ELEMENTS
is implicit. The audit elements are as follow:
COMMENT This permits use of the LOG COMMENT
statement in the DBEnvironment.
Comments are logged to the defined
COMMENT PARTITION. If this element
is not chosen, the LOG COMMENT
statement returns an error.
DATA This is the default element. It
causes audit log records to be
generated for any data operations
(INSERT, UPDATE, or DELETE) on
tables that are in an audit
partition of the DBEnvironment
other than NONE. (Tables can be
specified to be in partition NONE
and thus not participate in the
audit logging process.)
DEFINITION This includes audit logging of the
following statements:
CREATE TABLE
ALTER TABLE
DROP TABLE
CREATE INDEX
DROP INDEX
CREATE VIEW
DROP VIEW
CREATE RULE
DROP RULE
CREATE PROCEDURE
DROP PROCEDURE
TRANSFER OWNERSHIP
CREATE GROUP
DROP GROUP
CREATE DBEFILESET
DROP DBEFILESET
CREATE PARTITION
DROP PARTITION
TRUNCATE TABLE
STORAGE This includes audit logging of the
following statements:
CREATE DBEFILE
DROP DBEFILE
ADD DBEFILE TO DBEFILESET
REMOVE DBEFILE FROM DBEFILESET
CREATE TEMPSPACE
DROP TEMPSPACE
AUTHORIZATION This includes audit logging of the
following statements:
GRANT
REVOKE
ADD TO GROUP
REMOVE FROM GROUP
SECTION This includes audit logging of the
creation and deletion of permanent
sections. Permanent sections are
created when a program is
preprocessed, and are deleted by
the DROP MODULE statement. Logging
of section creation does not
include any SETOPT information
associated with the section. See
the SETOPT statement in the "SQL
Statements" chapter.
ALL This is equivalent to specifying
COMMENT DATA DEFINITION STORAGE
AUTHORIZATION SECTION AUDIT
ELEMENTS as described above.
NewLogDefinition is a clause that provides ALLBASE/SQL with the
information needed to create one or more new log
files. The syntax for this clause is presented
in the next section.
SQL Syntax--NewLogDefinition
LOG DBEFILE DBELog1ID [AND DBELog2ID]
WITH PAGES = DBELogSize,
NAME = 'SystemFileName1'
[AND 'SystemFileName2']
Parameters--NewLogDefinition
LOG DBEFILE describes the two log files if the DUAL LOG
option is specified, or a single log file
otherwise.
DBELog1ID and are the basic names identifying the log files.
DBELog2ID
DBELogSize specifies the number of 512-byte pages in one log
file. If dual logging is used, both logs must be
the same size. The DBE log size should be at
least 250 pages and no greater than 524,287
pages. The default is 250. If you choose an odd
number of pages, the number is rounded up to an
even number.
SystemFileName1 and identify how the logs are known to the operating
SystemFileName2 system. The logs are created in the same group
and account as the DBECon file by default. You
can specify a different group name for each log
file, but the account name, if given, must be the
same as that of the DBECon file. If a log file
by the same name already exists, use SQLUtil to
purge it before issuing the START DBE NEWLOG
statement.
Description
* The usual reason for using START DBE NEWLOG is to increase or
decrease log file space or to invoke dual logging.
* When you choose an odd number of log pages using the WITH PAGES
clause of the new log definition, the number is rounded up to an
even number, which is displayed in SHOWLOG.
* Do not use this statement unless you are certain that the
preceding termination of ALLBASE/SQL was normal and all active
sessions terminated normally. Before using the START DBE NEWLOG
statement, it is recommended that you issue a START DBE statement
in single user mode to ensure the DBEnvironment is in a consistent
state before the existing log(s) are disassociated from the
DBEnvironment.
* Use the ARCHIVE option only as a part of a static backup procedure
with archive logging. Refer to the "Backup and Recovery" chapter
in the ALLBASE/SQL Database Administration Guide for more
information. The preferred method for starting archive logging is
to use the SQLUtil STOREONLINE command after initial loading of
the DBEnvironment is complete.
* No DBE sessions for the DBEnvironment can be in effect when this
statement is processed.
* Timeout values set in the START DBE NEWLOG statement remain in
effect only as long as there is a DBEnvironment session connected
to the DBEnvironment, and do not modify the values stored in the
DBECon file.
* If no MAXIMUM TIMEOUT limit is specified, the MAXIMUM TIMEOUT
limit stored in the DBECon file remains in effect. If no DEFAULT
TIMEOUT value is specified, the DEFAULT TIMEOUT value stored in
the DBECon file remains in effect.
* If MAXIMUM TIMEOUT = NONE, infinity (no timeout) is assumed. If
DEFAULT TIMEOUT = MAXIMUM, the value of MAXIMUM TIMEOUT is
assumed. The DEFAULT TIMEOUT value may not exceed the MAXIMUM
TIMEOUT value.
* The following parameters defined in the START DBE NEW statement
are stored in the DBECon file:
* DBEnvironment language
* User mode (single versus multi)
* Number of data buffer pages
* Number of log buffer pages
* Maximum transactions
* Maximum timeout value
* Default timeout value
* Number of runtime control block pages
* DBEFile0 system file name
* Log system file name(s)
* Audit logging (chosen versus not)
* Audit name
* Audit elements
* Default partition
* Comment partition
* Maximum number of partitions
* You can reconfigure a DBEnvironment by using SQLUtil to alter
DBECon file parameters. All parameters except the audit
information (logging, audit elements, name, default, comment and
maximum partition), or the name of the DBECon file and DBEFile0
may be changed. Refer to the ALLBASE/SQL Database Administration
Guide for additional information.
* If AUDIT LOG is specified, the clauses AUDIT NAME, DEFAULT
PARTITION, and MAXPARTITIONS must also be specified. Further, if
no AUDIT ELEMENTS are specified, DATA is used as a default.
* Use of the clause ALL AUDIT ELEMENTS implies specification of all
of the audit elements.
* The usual reason for using START DBE NEWLOG is to increase or
decrease log file space, to invoke dual logging or audit logging,
or to alter audit logging parameters.
* Audit parameters set in the START DBE NEWLOG statement modify the
values stored in the DBECon file.
* If an audit parameter is not specified in the statement, the audit
parameter remains unchanged. The parameters AUDIT NAME, DEFAULT
PARTITION, MAXPARTITIONS, COMMENT PARTITION, and AUDIT ELEMENTS
can be changed at any time through the START DBE NEWLOG statement.
* If AUDIT LOG is not specified in this statement, the default is
that it is disabled. Thus if the DBEnvironment had audit logging
enabled and then specified a START DBE NEWLOG statement without
AUDIT LOG, audit logging would then be disabled.
* Changing MAXPARTITIONS on a START DBE NEWLOG prevents roll forward
recovery through prior log files, since their structure will
differ from the new logs' structure. The same is true of going
from non-audit logs to audit logs and vice versa. Therefore, it
is recommended that an audit DBEnvironment be designed with a
large enough MAXPARTITIONS when it is created.
* Additional log files should be created with the SQLUtil ADDLOG
command.
* Refer to the ALLBASE/SQL Database Administration Guide for
additional information on log file management.
Authorization
You need to be the DBECreator to issue the START DBE NEWLOG statement.
Example
The DBEnvironment is restored to a consistent state. Any transactions
incomplete when the DBEnvironment was last shut down are rolled back, and
work done by completed transactions is committed.
START DBE 'PartsDBE.SomeGrp.SomeAcct'
SQLUtil is used to delete the existing log files: PartsLg1 and PartsLg2.
STOP DBE
The log files are reinitialized.
START DBE 'PartsDBE.SomeGrp.SomeAcct' MULTI NEWLOG DUAL LOG
LOG DBEFILE PartsDBELog1 AND PartsDBELog2
WITH PAGES = 250, NAME = 'PartsLg1' AND 'PartsLg2'
The DBEnvironment is restored to a consistent state. Any transactions
incomplete when the DBEnvironment was last shut down are rolled back, and
work done by completed transactions is committed.
START DBE 'PartsDBE'
STOP DBE
After the DBEnvironment is stopped, the log files can be purged.
New log files are reinitialized and audit logging is enabled.
START DBE 'PartsDBE' MULTI NEWLOG DUAL
AUDIT LOG,
AUDIT NAME = 'PrtsDBE1',
DEFAULT PARTITION = 1,
MAXPARTITIONS = 20,
DATA AUDIT ELEMENTS,
LOG DBEFILE PartsDBELog1 AND PartsDBELog2
WITH PAGES = 1000, NAME = 'PartsLg1' AND 'PartsLg2'
You must create additional log files with the SQLUtil ADDLOG command.