Adabas Vista Parameters

This section describes the Adabas Vista parameters.

General Parameters File Partitioning Parameters File Translation Parameters Target Category Parameters
Command Limit Access Target Database Number First-level Null Definition Policy
Source Database Number Adabas TOPISN Target File Number Category Adjustment Policy
Source File Number Critical Mandatory Second-level Null Definition Policy
Source Name Enable ISN Positioning Priority  
  Maximum Number Partitions Redirect  
  Partition Database Number No Translation  
  Partition File Number User Info  
  Partition ID    
  Partition ID Assignment    
  Partitioning Field    
  Partitioning Field High Value    
  Shared Partition    
  Source Type    
  Store Control Option    
  User Partition Concurrency    

General

Command Limit

Description Possible Values Default

The maximun number of commands permitted against a source file. Any command that exceeds this number will result in an error code. The default value 0 indicates no limit.

  0

Source Database Number

Description Minimum Maximum Default

The number of a database which identifies an Adabas Vista file. This number is used in conjunction with a source file number.

Note:
In Natural systems, this is the database number defined in a DDM.

1 65535 0

Source File Number

Description Minimum Maximum Default

The file number for an Adabas Vista file. This number is used in conjunction with a source database number.

Note:
In Natural systems, this is the file number defined in a DDM.

1 65535 0

Source Name

Description Possible Values Default

A unique name identifying a particular Adabas Vista file without referring to the source database and file number. The name must be unique across all published partitioned file definitions. The name must also be unique across all published translation rules.

(optional)

  none

Partitioning Parameters

Access

Description Possible Values Default

Controls the type of access for each partition of a partitioned file.

The following values are permitted:

  • FULL: read/write access is permitted

  • READ: read-only access is permitted

  • ONLY: partition is set to FULL and all other partitions to NONE

  • NONE: no access is permitted

See section Partition Restriction for more information.

FULL | READ | ONLY | NONE FULL

Adabas TOPISN

Description Minimum Maximum Default

The maximum Adabas ISN permitted for a partition.

Adabas Vista enforces the specified maximum during read and store processing.

The initial maximum is determined by the Maximum Number of Partitions / Default Partition TOPISN, established when the partitioned file is first defined.

This parameter may be used to provide a lower value in order to maintain specific partition sizes that may have been derived from recovery and maintenance considerations.

Note:
The Adabas TOPISN value is a limit on the maximum ISN for a partition and not the maximum number of records.

1 2,147,483,647 16,777,215

Critical

Description Possible Values Default

Indicates the action to be taken whenever a partition becomes unavailable.

Possible values are:

  • YES: the user cannot tolerate the partition's unavailability. Normal user operation is interrupted when access is attempted (with the corresponding Adabas response code).

  • NO: the user can tolerate the partition's unavailability. Data in that partition is ignored until the partition becomes available again. The partitions that return one of the partition unavailable response codes (17, 48, 148) when accessed are logged and can subsequently be identified using the CRITREP function of the Adabas Vista API.

See section Partition Outage for more information.

YES | NO YES

Enable ISN Positioning

Description Possible Values Default

Indicates whether or not ISN positioning is to be used when an Adabas Vista ISN is provided as an optional start ISN for L2/5 and L3/6 commands or as a minimum ISN value for Sx commands.

If an L1 command with Command Option 2 set to I is issued with a starting Adabas Vista ISN of zero and this parameter is set to YES, reading begins from the first partition.

YES | NO YES

Maximum Number of Partitions (Default Partition TOPISN)

Description Minimum Maximum Default

The maximum number of partitions available for use by a partitioned file.

Only those partitions relevant to current processing requirements need to be defined. However, the future requirements of the partitioned file must also be considered when determining the value for this parameter.

Because of the structure of the Adabas Vista ISN, this parameter directly affects

  • the amount of space reserved in the ISN field for the Partition ID; and

  • the default Adabas TOPISN for each partition.

The default Adabas TOPISN imposed by this parameter is calculated and displayed in order to help determine the correct balance between the maximum number of partitions and the resulting Adabas TOPISN partition limit.

1 65535 255

Partitioning Field

Description Possible Values Default

The Adabas name, length, and format of the field used to distribute the data into separate partitions.

The partitioning field of a partitioned file can be a standard Adabas field, a descriptor, a superdescriptor, a subdescriptor, or a dummy field.

It may not be

  • a multiple value field;

  • an item in a periodic group;

  • of format F, G, or W;

  • a superdescriptor with one or more parents of format W;

  • of variable length (length of zero in the FDT); or

  • a field with the long alphanumeric (LA) attribute.

The Adabas UQ attribute is supported only for fields defined as the partitioning field, and only if the appropriate Adabas field name is defined with the UQ option in the Adabas FDT for each partition.

The specified Adabas short name, length, and format must be identical to its field definition in the Adabas FDT with one exception: if the partitioning field is a superdescriptor with format A (that is, one of its parent fields is defined with format A), then a format of B may need to be specified to enable correct specification of the Partitioning Field High Value, if any component of the superdescriptor cannot be represented by character values. The field formats may be obtained from either the full or demo version of Adabas Online System, or by running the Adabas ADAREP utility.

Note:
An optional name for the partitioning field may be provided in the "display as" field to make the partitioning field easier to identify.

 see text none

Partitioning Field High Value

Description Possible Values Default

This parameter is mandatory for each partition. It is used to specify the highest value of the partitioning field that can exist in the partition. The value must be specified in accordance with the defined partitioning field's format and length.

If the partitioning field's format has been defined as

  • alphanumeric (A), normal alphanumeric values may be specified.

  • packed decimal (P) or unpacked decimal (U), the decimal value must be preceded, if applicable, by a '-' or optionally a '+' sign.

  • binary (B), the value must be specified in hexadecimal format (that is, two digits for each byte). In the case of a superdescriptor with a U or P format parent, the sign F or D must be used to indicate a positive or negative value, respectively.

 see text none

Some examples:

Defined Partitioning Field Adabas Field Type Specified High Value
AA,2,A standard field ZZ
BB,2,B standard field FFFF
PP,2,P standard field 999
UU,2,U standard field 99
S1,4,B SUPDE=UU(1-2),AA(1-2) F9F9E9E9
S2,4,B SUPDE=BB(1-2),PP(1-2) FFFF999F

Note:
The physical data in each Adabas file must be consistent with the implied range specified by the Partitioning Field High Value defined for the partition. This can be achieved by using:

  • external sort; or

  • the Adabas ADAULD utility and the SELCRIT/SELVAL selection criteria parameters.Refer to the Adabas Utilities documentation for information.

Partition Database Number

Description Minimum Maximum Default

A database number to which Adabas commands issued against an Adabas Vista partitioned file may be directed.

1 65535 0

Partition File Number

Description Minimum Maximum Default

A file number to which Adabas commands issued against an Adabas Vista partitioned file may be directed.

1 65535 0

Partition ID

Description Minimum Maximum Default

A number that uniquely identifies a partition within a partitioned file.

The Partition ID is used together with the Adabas ISN to form an Adabas Vista ISN. This Adabas Vista ISN is returned to the application in place of the Adabas ISN.

The allocation of a Partition ID depends on the Partition ID Assignment of the partitioned file.

The actual maximum value of the Partition ID is determined by the Maximum Number of Partitions established when the partitioned file is first defined.

When such an Adabas Vista ISN is received from the application (for example, in the case of an update), Adabas Vista interprets the ISN and is able to redirect the update to the correct partition.

Refer to the section Adabas Vista ISN for more information.

1 65535 none

Partition ID Assignment

Description Possible Values Default

Indicates whether Partition ID assignment is to be performed by Adabas Vista automatically or by the user manually.

User assignment, which requires that the user specify a Partition ID for each partition, may be useful when an application stores the Adabas Vista ISN as data and the likelihood exists that the structure of the partitioned file may change; for example, inserting new partitions or splitting current partitions.

Refer to the section Adabas Vista ISN for more information.

VISTA | USER VISTA

Shared Partition

Description Possible Values Default

This parameter can be used to enable the Adabas Vista shared partition feature (also referred to as the multipart feature).

See also the section Partition Sharing.

YES | NO NO

Example:

Adabas Vista file partitioning normally maps each partition to a unique Adabas file:

Partition 1: DBID=1,FNR=10,Partitioning Field High Value=A
Partition 2: DBID=1,FNR=11,Partitioning Field High Value=B
Partition 3: DBID=1,FNR=12,Partitioning Field High Value=C

The shared partition feature can be used to share an Adabas file between partitions:

Partition 1: DBID=1,FNR=10,Partitioning Field High Value=A,Shared Partition=YES
Partition 2: DBID=1,FNR=11,Partitioning Field High Value=B
Partition 3: DBID=1,FNR=10,Partitioning Field High Value=C,Shared Partition=YES

The above example shows the partition definitions necessary to split all records with a partitioning field value of 'B' from the main file (database 1, file 10) onto a new file (database 1, file 11).

Notes:

  1. The partition definitions must still reflect collating sequence.

Source Type

Description Possible Values Default
The type of partitioned file. S | E S

Possible values:

Value Description
S This source file is a Standard partitioned file.
E

This source file is an Extreme partitioned file.

For more information, refer to Using Extreme partitioned files in the Programming Guidelines.

Store Control Option

Description Possible Values Default

Controls the placement of new records into a partitioned file.

When storing a record to a partitioned file, the value for the partitioning field is extracted from the Adabas record buffer and used to direct the new record to the correct partition: this is termed normal placement. For store operations that do not specify a partitioning field or provide a null value for it, Store Control Option may be used to direct the record to a partition.

1 | 2 | F | L 1

The value provided with this option determines the placement of new records according to the presence, absence, or value of the partitioning field within the Adabas format/record buffer. The following table indicates the actions performed for each possible value:

Note:
If your requirements are not provided for in the table, contact Software AG support for further assistance.

Value Partitioning Field with non-null value Partitioning Field with null value No Partitioning Field
1 normal placement normal placement reject
2 normal placement reject reject
F normal placement directed to first partition directed to first partition
L normal placement directed to last partition directed to last partition

Note:
In cases where a null value is provided for the partitioning field and the record is subsequently stored, retrieval of the record using the partitioning field depends on the null value suppression (NU) option of the field as defined in the Adabas FDT.

Note:
It is recommended that only distributed access (that is, access not based on the partitioning field) be performed on those partitioned files defined with options F or L. Otherwise, records may be retrieved out of sequence.

User Partition Concurrency

Description Minimum Maximum Default

The number of concurrent Adabas Command ID sequences that a user may have outstanding for each partition.

4 255 8

Translation Parameters

Target Database Number

Description Minimum Maximum Default

The number of the database to which an Adabas command that is subject to an Adabas Vista translation rule is to be re-directed.

1 65535 0

Target File Number

Description Minimum Maximum Default

The number of the file to which an Adabas command that is subject to an Adabas Vista translation rule is to be re-directed.

1 65535 0

Mandatory

Description Possible Values Default

When resolving a source file into a translation target (by reference to the translation file pages defined in the client’s runtime controls), Adabas Vista will always select the first translation rule it finds with a mandatory attribute of Y.

Y | N N

Priority

Description Minimum Maximum Default

When resolving a source file into a translation target (by reference to the file translation pages defined in the client’s runtime controls), and a translation rule exists in more than one page – none of which have the mandatory attribute set to Y - then Adabas Vista will select the translation rule with the highest priority setting.

0 255 0

Redirect

Description Possible Values Default

To provide additional flexibility during translation processing, the active target category (mode) can be altered using Redirect.

Any such redirection is maintained for the remainder of the translation process.

  none

No Translation

Description Possible Values Default

You can explicitly prevent translation by leaving the target database and file and redirect category empty and marking the "None" attribute with any non-blank character. Note that this setting is a conscious action to prevent translation, unlike leaving a null entry. As such, notice will be taken of this setting during page merge and translation resolution processing.

May only be marked if no target or redirect information is specified. see text

User Info

Description Possible Values Default

This field is provided for use by the DBA.

(optional)

  none

Target Category Parameters

First-level Null Definition Policy

Description Possible Values Default

Specifies how Adabas Vista should react at runtime if the translation process for the active target category (mode) results in a “null” outcome. Options are:

  • Allow calls for which no rules exist (default)

  • Reject with response 249, subcode 106 at end of page-merge

  • Use the rule from a nominated category

Select one of the options see text

Category Adjustment Policy

Description Possible Values Default

Specifies whether Adabas Vista at runtime should honour translation rules that change the active target category (mode). Options are:

  • Allow a rule in a page to change (redirect) category (default)

  • Reject with response 249, subcode 107

Select one of the options see text

Second-level Null Definition Policy

Description Possible Values Default

Specifies how Adabas Vista should react at runtime if the first-level null definition policy redirects to another target category (mode) which in turn results in a “null” outcome. Options are:

  • Allow calls for which no rules exist (default)

  • Reject with response 249, subcode 108 at end of page-merge

Select one of the options see text