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The START DBE NEW statement configures and establishes a connection with
a new 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. Startup parameters are
also stored in the DBECon file.
ISQL or Application Programs
START DBE 'DBEnvironmentName' [AS 'ConnectionName'][MULTI]NEW
[{DUAL
AUDIT}[...] LOG
BUFFER = DataBufferPages, LogBufferPages)
LANG = LanguageName
TRANSACTION = MaxTransactions
MAXIMUM TIMEOUT = {TimeoutValue [SECONDS
MINUTES]
NONE }
DEFAULT TIMEOUT = {TimeoutValue [SECONDS
MINUTES]
MAXIMUM }
RUN BLOCK = ControlBlockPages]
DEFAULT PARTITION = {DefaultPartitionNumber
NONE }
COMMENT PARTITION = {CommentPartitionNumber
DEFAULT
NONE }
MAXPARTITIONS = MaximumNumberOfPartitions
AUDIT NAME = 'AuditName'
{COMMENT
DATA
DEFINITION
STORAGE
AUTHORIZATION
SECTION
ALL }[...] AUDIT ELEMENTS
DBEFile0Definition
DBELogDefinition ][,...]
- DBEnvironmentName
identifies the DBEnvironment name used in the CONNECT
statement. This name also identifies the DBECon file that stores the
values of all parameters specified in the START DBE NEW statement
that are also used in the CONNECT statement. Unless you specify an
absolute path name, ALLBASE/SQL assumes the name is relative to your
current working directory.
- ConnectionName
associates a user specified name with this connection.
ConnectionName 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 by multiple users
simultaneously. If omitted, the DBEnvironment can be accessed only in
single-user mode.
- DUAL LOG
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;
if an error is detected, the write continues on the good log only.
Normally, only one log is read, but if an error is encountered,
ALLBASE/SQL switches to the other log. Data integrity is maintained
provided is at least one good copy of each log record is on at least
one of the logs.
- AUDIT LOG
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 512-byte log buffer pages
to be used. You 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.
- LANG
specifies the language for the DBEnvironment. If
the name of the language contains a hyphen, use double quotes in
specifying it, as in the following (c-french means Canadian French):
LANG = "c-french"
- MaxTransactions
specifies the maximum number of concurrent transactions
to be supported. You can specify a value from 2 to 240. The default
is 50. 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 point
in time you should allow 2 concurrent transactions for just being
connected to the DBE.
- MAXIMUM TIMEOUT
specifies the maximum user timeout value that is
stored in the DBECon file. The default is the MAXIMUM.
- DEFAULT TIMEOUT
specifies the default user timeout value that is
stored in the DBECon file. The default is NONE (infinity).
- 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. The value specified is stored 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. This
clause must be specified if AUDIT LOG is specified.
DefaultPartitionNumber must be in the range 1 and 32767.
If NONE is specified, tables in the DBEnvironment that are in the default
partition do not generate audit log records. See the CREATE TABLE
and ALTER TABLE statements for information on assigning a table to
a partition.
- 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.
- MaximumNumberOfPartitions
specifies the maximum number of partitions for the DBEnvironment. This
clause must be specified if AUDIT LOG has been specified.
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 (not counting the DATA 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 more partitions or audit elements
in the future.
- 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 follows:
- COMMENT
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
is the default element. It causes audit log records to be done 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
includes audit logging of the following statements:
CREATE TABLE
ALTER TABLE
DROP TABLE
CREATE 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
includes audit logging of the following statements:
CREATE DBEFILE
DROP DBEFILE
ADD DBEFILE TO DBEFILESET
REMOVE DBEFILE FROM DBEFILESET
CREATE TEMPSPACE
DROP TEMPSPACE
- AUTHORIZATION
includes audit logging of the following statements:
GRANT
REVOKE
ADD TO GROUP
REMOVE FROM GROUP
- SECTION
includes audit logging of the creation and deletion of permanent
sections or procedures. Permanent sections or procedures are created
when a program is preprocessed, and are deleted by the DROP
MODULE statement. The DROP PROCEDURE statement deletes
procedures. Logging of section creation does not include any
SETOPT information associated with the section. See the
SETOPT statement.
- ALL
is equivalent to specifying COMMENT DATA DEFINITION STORAGE
AUTHORIZATION SECTION AUDIT ELEMENTS as described above.
- DBEFile0Definition
is a clause that provides the information ALLBASE/SQL needs to
automatically create DBEFile0 and add it to the SYSTEM DBEFileSet. The
syntax for this clause is presented separately below. If
DBEFile0Definition is omitted, ALLBASE/SQL assumes the
following:
DBEFILE0 DBEFILE DBEFILE0
WITH PAGES = 150,
NAME = 'DBEFile0'
By default, DBEFile0 resides in the same directory as the DBECon file.
However, you can use the SQLUtil MOVEFILE command to move it to another
directory.
- DBELogDefinition
is a clause that provides ALLBASE/SQL with the information needed to
create one or more log files. Syntax for this clause is presented
separately below. If DBELogDefinition is omitted,
ALLBASE/SQL assumes the following:
LOG DBEFILE DBELOG1
WITH PAGES = 250,
NAME = 'DBELOG1
By default, DBELOG1 resides in the same directory as the DBECon
file.
DBEFILE0 DBEFILE DBEFile0ID
WITH PAGES = DBEFile0Size,
NAME = 'SystemFileName1'
- DBEFILE0 DBEFILE
describes a DBEFile known as DBEFile0, which contains the portion of
the system catalog needed for activating a DBEnvironment, including
definitions of other DBEFiles. Each DBEnvironment must have a DBEFile0
associated with a unique SystemFileName, which is
assigned in this clause.
- DBEFile0ID
is the basic name identifying DBEFile0.
- DBEFile0Size
specifies the number of 4096-byte pages in DBEFile0. You can specify
from 150 to 524,287 pages. The default and minimum is 150.
- SystemFileName1
identifies how DBEFile0 is known to the operating system. DBEFile0 is
created relative to the directory specified in the DBEnvironment name
parameter unless an absolute path name is specified. The default file
name is 'DBEFile0'.
LOG DBEFILE DBELog1ID [AND DBELog2ID]
WITH PAGES = DBELogSize,
NAME = 'SystemFileName2' [AND 'SystemFileName3']
- LOG DBEFILE
describes the two log files if the DUAL LOG option is specified, or a
single log file otherwise. If you give information for two log files but
omit the DUAL LOG option, the information for the second log file is
ignored.
- DBELog1ID and DBELog2ID
are the basic names identifying the log files.
- 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.
- SystemFileName2 and SystemFileName3
identify how the logs are known to HP-UX. The logs
are created relative to the directory specified in the DBEnvironment
name parameter unless an absolute path name is specified.
When you issue this statement, ALLBASE/SQL creates a DBECon file
with the same name as the DBEnvironmentName.
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
The following additional parameters are stored in the DBECon file:
The autostart flag determines how DBE sessions are
started. If the value of autostart is ON, a DBE session can be
established by using the CONNECT statement. If the value
of autostart is OFF, the START DBE statement must be used
to start up a DBEnvironment; if the START DBE statement
contains the MULTI option, other users establish DBE sessions
with the CONNECT statement. Autostart is on by
default.
The DDL Enabled flag determines whether data definition
is enabled for the DBEnvironment. The DDL Enabled flag is set to
YES by default. See "Maintenance" in the ALLBASE/SQL
Database Administration Guide for additional information
about the DDL Enabled flag.
The archive mode flag determines whether the
DBEnvironment is operating in archive mode. In archive mode,
ALLBASE/SQL does rollforward logging. The rollforward log can be
used to redo transactions in case it is necessary to restore the
DBEnvironment from a backed up (archival) copy. When archive mode
has the value of OFF, log space can be recovered by using the
CHECKPOINT statement. If you want to do rollforward
recovery, you must always operate in archive mode. Rollback
recovery is enabled regardless of the archive mode. Archive mode
is off by default.
When you choose an odd number of log pages using the WITH PAGES
clause of the DBEFile definitions, the number is rounded up to an
even number, which is displayed in SHOWLOG.
The size of DBEFile0 is fixed at the time you configure
a DBEnvironment and cannot be changed. If you need more space at
a later time, add a DBEFile to the SYSTEM DBEFileSet.
DBEFile0 cannot be restricted to containing data
pages only or index pages only; the storage in DBEFile0 is used
for both data and index pages.
You can reconfigure a DBEnvironment by using SQLUtil
to alter DBECon file parameters. All parameters except the name
of the DBECon file and DBEFile0 may be changed. Refer to the
ALLBASE/SQL Database Administration Guide for
additional information.
The files created with this statement are owned by hpdb
and have the following permissions:
-rw------
If no MAXIMUM TIMEOUT limit is specified, or if
MAXIMUM TIMEOUT = NONE, infinity (no timeout) is assumed. If no
DEFAULT TIMEOUT value is specified, or if DEFAULT TIMEOUT = MAXIMUM,
the value of MAXIMUM TIMEOUT is assumed. The DEFAULT TIMEOUT value
may not exceed the MAXIMUM TIMEOUT value.
You cannot use the START DBE NEW statement on a diskless
machine. A DBEnvironment for use in diskless clusters must be created
on the cluster server. Refer to the ALLBASE/NET User's
Guide for further information.
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. If
no COMMENT PARTITION is specified, DEFAULT is assumed. The DEFAULT
PARTITION or the COMMENT PARTITION can be specified as NONE.
Use of the clause ALL AUDIT ELEMENTS implies specification
of all of the audit elements.
Additional log files should be added using the
SQLUtil ADDLOG command.
No authorization is needed for using the START DBE NEW statement.
hpdb must have write permission in the target directory
for all the files the START DBE NEW statement creates.
The DBEnvironment for the sample database is a multiuser DBEnvironment
in which as many as five transactions can execute concurrently.
The DBEnvironment is initially configured for two rollback logs
and a DBEFile0 residing in PartsF0. The number of runtime control
pages to be used is 500. By default, autostart mode is set to ON.
START DBE '../sampledb/PartsDBE' MULTI NEW
DUAL LOG,
TRANSACTION = 5,
DBEFILE0 DBEFILE PartsDBE0
WITH PAGES = 150, NAME = 'PartsF0',
LOG DBEFILE PartsDBELog1 AND PartsDBELog2
WITH PAGES = 256, NAME = 'PartsLg1' AND 'PartsLg2',
RUN BLOCK = 500
The DBEnvironment has all the above parameters listed and
it is enabled for audit logging. All DML and DDL changes in the
DBEnvironment are subject to audit logging since all audit elements
are selected. Up to 20 partitions can coexist in this DBEnvironment,
allowing for 14 data partitions in addition to the other elements' partitions.
The log files should be made large enough for the added audit log records.
START DBE '../sampledb/PartsDBE' MULTI NEW
DUAL AUDIT LOG,
TRANSACTION = 5,
RUN BLOCK = 500,
AUDIT NAME = 'PrtsDBE1',
DEFAULT PARTITION = 1,
COMMENT PARTITION = 2,
MAXPARTITIONS = 20,
ALL AUDIT ELEMENTS,
DBEFILE0 DBEFILE PartsDBE0
WITH PAGES = 150, NAME = 'PartsF0',
LOG DBEFILE PartsDBELog1 AND PartsDBELog2
WITH PAGES = 1000, NAME = 'PartsLg1' AND 'PartsLg2'
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