ALTDBE

Changes the startup parameters for a DBEnvironment.

Scope

SQLUtil Only

SQLUtil Syntax

>> ALTDBE DBEnvironment Name: DBEnvironmentName Maintenance Word: MaintenanceWord AutoStart Mode (on/off) (opt): AutoStartMode User Mode (single/multi) (opt): UserMode DDL Enabled (y/n) (opt): DDLEnabled No. of Runtime Control Block Pages (opt): ControlBlockPages No. of Data Buffer Pages (opt): DataBufferPages Data Buffer Pages Memory Resident (y/n) (opt): MemoryResidentEnabled No. of Log Buffer Pages (opt): LogBufferPages Max. Transactions (opt):MaxTransactions Maximum Timeout (opt): [ MaximumTimeout [ SECONDS MINUTES ] NONE ] Default Timeout (opt): [ DefaultTimeout [ SECONDS MINUTES ] MAXIMUM ] Authorize Once per Session (on/off) (opt): AuthorizeOnce Alter DBEnvironment Startup Parameters (y/n)? { Y [es] N [o]}




	NOTE: You must stop the DBEnvironment before you can issue the ALTDBE command.

Parameters

DBEnvironmentName: is the name of the DBEnvironment whose startup parameters are to be altered.
MaintenanceWord: is the maintenance word of the DBEnvironment.
AutoStartMode: is ON to enable auto starting of a multiuser DBEnvironment session when a CONNECT command is given. It is OFF to disable this feature. The default is ON.
UserMode: is SINGLE to specify that the DBEnvironment should be started in single-user mode when AutoStart is enabled. It is MULTI to specify multiuser operation. The default is determined by the value you supply in the START DBE NEW command. If you do not supply a value, the default is SINGLE.
DDLEnabled: is YES to enable data definition language (DDL), or NO to disable DDL. The default is YES.
ControlBlockPages: is the number of 4096-byte pages to allocate to the pool of shared memory used by DBCore services in a multi-user DBEnvironment.
DataBufferPages: is the number of 4096-byte data buffer pages for holding data from tables and indexes during program execution.
MemoryResidentEnabled: is YES to specify that data buffer pages will remain resident in memory. It is NO to specify that data buffer pages will not be memory resident (they will be swapped in and out of memory as needed by ALLBASE/SQL). The default is NO.
LogBufferPages: is the number of 512-byte log buffers for holding log records during program execution.
MaxTransactions: is the maximum number of concurrent transactions to be supported.
MaximumTimeout: is an integer literal greater than zero. If the MaximumTimeout is not qualified by MINUTES, SECONDS is assumed. If MaximumTimeout is set to NONE, no timeouts are assumed. The default is NONE.
DefaultTimeout: is an integer literal greater than zero. If the DefaultTimeout is not qualified by MINUTES, SECONDS is assumed. If DefaultTimeout is set to MAXIMUM, its value is the same as MaximumTimeout. The default value of DefaultTimeout is also MaximumTimeout.
AuthorizeOnce: is set ON to permit users of ISV (independent software vendor) toolsets to obtain improved performance with dynamic queries. If you have preprocessed an application with the (DYNAMIC) option, or if you are using an ISV toolset, set this flag ON if you want authorization checks on your dynamic queries to be performed only the first time the query is executed during the user session. Set OFF if you want ALLBASE/SQL to do authorization checks on a dynamic query each time it is executed. The default is OFF.

Description

The ALTDBE command updates the parameters required for DBEnvironment startup. You are prompted for new values for the parameters one by one; entering a Return retains the old value.
Startup parameters have been initially defined by a START DBE NEW command which creates the DBEnvironment and stores these parameters in the DBECon file. These parameters will be used when the DBEnvironment is accessed by either a START DBE or a CONNECT command.
Setting the MemoryResidentEnabled flag to YES is useful for database servers where very little is going on besides database work, and the database buffers occupy a small fraction of real memory in the system.
You get better performance from pseudo-mapped DBEFiles if you set the MemoryResidentEnabled flag to YES.
This command can only be executed when the DBEnvironment is not in use.
You cannot change archive mode with ALTDBE. Refer to the section "Choosing an Approach to Backup and Recovery" in the "Backup and Recovery" chapter.




	NOTE: Scripts using the ALTDBE command that were prepared for use with releases of ALLBASE/SQL prior to F.0 will not work with this release unless you edit them to include responses for the memory resident data buffer flag, default and maximum user timeout, and the authorize once per session flag. Scripts using ALTDBE that were prepared for use with releases of ALLBASE/SQL prior to E.1 will not work unless you edit them to remove the response for archive mode and include responses for the memory resident data buffer flag, default and maximum user timeout, and the authorize once per session flag.

Authorization

You must provide the correct maintenance word or be the DBECreator to use this command.

Example

 

   >> altdbe



   DBEnvironment Name:  PartsDBE

   Maintenance Word:  MaintWd

   AutoStart Mode (on/off) (opt):  on

   User Mode (opt):  multi

   DDL Enabled (y/n) (opt):  yes

   No. of Runtime Control Block Pages (opt): 37

   No. of Data Buffer Pages (opt):  100

   Data Buffer Pages Memory Resident (y/n) (opt): no

   No. of Log Buffer Pages (opt):  24

   Max. Transactions (opt):  5

   Maximum Timeout (opt): 10

   Default Timeout (opt): 5

   Authorize Once per Session (opt): on

   Alter DBEnvironment Startup Parameters (y/n)?  yes



   DBEnvironment startup parameters altered.