File Management Table

Preparing Control Information › File Management Table

File Management Table

Purpose

The file management table is a control block that establishes a one-to-one correspondence between the VSAM data set referenced by the application program and the CA IDMS/DB database record accessed by CA IDMS VSAM Transparency. Each CA IDMS VSAM Transparency file is required to have a file management table. User-supplied parameters are compiled with the FMT compiler and linked into the CA IDMS/DB load library or z/VSE CA IDMS/DB library.

You must define and compile one FMT for each CA IDMS VSAM Transparency data set used by the VSAM application programs. FMT control statements must be entered in the order presented in the syntax below.

See the tables located under Usage later in this section for VSAM data set definitions, CA IDMS schema definitions and corresponding FMT compiler statements. See z/VSE CICS SYSESVS Parameters later in this manual for z/VSE CICS SYSESVS file management parameters.

Syntax

►►──── FMT NAME is file-management-table-name ──.─────────────────────────────►

 ►──── FILE TYPE is ─┬─ KSDS ─────────────────────────────────────────────┬─.─►
                     ├─ ESDS ─────────────────────────────────────────────┤
                     ├─ RRDS ─────────────────────────────────────────────┤
                     └─ PATH -─┬────────────────────────────────────────┬─┘
                               └─ BASE -─┬───────────┬─ is ─┬─ KSDS ◄ ─┬┘
                                         └─ cluster ─┘      └─ ESDS ───┘

Required for KSDS and a PATH Only

►►─── KEY LENgth is vsam-key-length ──.───────────────────────────────────────►

 ►─── KEY POSition is vsam-key-displacement ──.───────────────────────────────►◄

Required and Valid for RRDS Only

►►─── RELative RECord NUMber POSition is control-field-displacement ──.────►◄

 ►──┬────────────────────────────────────────────┬──────────────────────────────►
    └─ BUFFERSPACE is front-end-buffer-space ─ . ┘

 ►──┬────────────────────────────────────────────────────┬────────────────────►─
    └─ VSAM RECord LENgth is record-length variable ─ . ─┘

 ►──┬─────────────────────────────────────┬───────────────────────────────────►
    └─ FILE is ─┬───────────────────┬─ . ─┘
                ├─ REUSABLE ────────┤
                └─ NOT REUSABLE ◄ -─┘

 ►──┬─────────────────────────────────────────────────────────┬────────────────►
    └─ CALL exit-name ─┬───────────┬─ PROCessing REQuest ─ . ─┘
                       ├─ BEFORE ─┬┘
                       └─ AFTER -─┘

 ►──── RECord name is idms-record-name ── . ────────────────────────────────────►

 ►──┬─────────────────────────────────┬────────────────────────────────────────►
    └─ SET name is idms-set-name ─ . ─┘

 ►─┬───────────────────────────────────────────────┬──────────────────────────►◄
   └─ ERASE option is ─┬─ ERASE ALL ◄ ─────┬─ . ───┘
                       ├─ ERASE PERMANENT ─┤
                       ├─ ERASE SELECTIVE ─┤
                       ├─ ERASE RECORD ────┤
                       └─ DISCONNECT ──────┘

Expansion of record-length variable:

►►─┬───────────────────────────────────────────────────┬──────────────────────►─
   ├─ vsam-record-length ──────────────────────────────┤
   └─ VARiable UP TO MAXimum of maximum-record-length ─┘

Parameters

You must enter FMT control statements in the order presented below.

FMT NAME is file-management-table-name

Specifies a 1- to 8-character user-defined FMT name. FMT NAME is a required statement.

FILE TYPE is KSDS/ESDS/RRDS/PATH

Identifies the type of VSAM file that you are defining to CA IDMS/VSAM Transparency. FILE TYPE is a required statement.

More information:

For specific VSAM cluster statements that indicate the file type, see Usage

KEY LENgth is vsam-key-length

Specifies the length of the key of a KSDS record or a PATH. Vsam-key-length can be a 1- to 3-digit value in the range 1 through 255. Note that the KEY LENGTH statement is required for a KSDS and a PATH, and is invalid for a RRDS and an ESDS.

KEY POSition is vsam-key-displacement

Specifies the location of the key in a KSDS or PATH record. Vsam-key-displacement can be 1 to 5 digits in the range 0 through 32,767. (The first byte of a record is considered to be position zero.) This statement is required for a KSDS and a PATH; it is invalid for a RRDS and an ESDS.

BUFFERSPACE is front-end-buffer-space

Specifies the amount of buffer space to be reserved by the front-end module to receive the results of VSAM LOCATE MODE requests. Buffer space can be allocated for any of the data set types. If not specified, this variable defaults to the VSAM record length.

Front-end-buffer-space can be a 1- to 5-digit value that ranges from the maximum VSAM record length to 32,767.

CA IDMS VSAM Transparency automatically reserves buffer space by using the greatest of the following values:

The buffer space value specified in the access method control block (ACB)
The greater of the following two values:

((String number or number of data buffers specified in the ACB) * maximum VSAM record length)

The buffer space value specified in the FMT

VSAM RECord LENgth is vsam-record-length

Specifies the length of the VSAM record for any of the VSAM data set types. The length specified can be different from that of the CA IDMS/DB record. For a RRDS, the length specified should not include the control-field length.

VARiable UP TO MAXimum of maximum-record-length

Optional. Specifies the size of the largest possible record for a variable-length record. The numeric value can be 1 to 5 digits in the range 1 through 32,768.

FILE is REUSABLE/NOT REUSABLE

Specifies whether the file can be reset when opened. When a reusable file is opened RESET, all existing records are erased. The default is NOT REUSABLE. FILE IS REUSABLE/NOT REUSABLE does not apply to a RRDS.

CALL exit-name BEFORE/AFTER PROCessing REQuest

Names the exit routine that will be invoked either before or after DML calls are issued by CA IDMS VSAM Transparency. Exit-name can be 1 to 8 characters in length. Note that duplicate names are allowed within a single FMT or in different FMTs.

RELative RECord NUMber POSition is control-field-displacement

Specifies the position within an CA IDMS/DB record of a user-defined relative-record-number control field for an RRDS record. Control-field-displacement can be 1 to 5 digits in the range 0 through 32,764. (The first byte of a record is considered to be position zero.) RELATIVE RECORD NUMBER POSITION is a required statement for RRDS data sets and is invalid for KSDS, ESDS, and PATH data sets.

The user-assigned relative-record number constitutes an RRN control field that requires four additional bytes in the schema record definition. The control field must be placed at the end of the CA IDMS/DB record.

RECord name is idms-record-name

Names the CA IDMS/DB record that corresponds to a VSAM record of each data set type used. RECORD NAME can be 1 to 16 characters in length.

SET name is idms-set-name

Names the CA IDMS/DB system-owned indexed set. SET NAME is required for all file types, with the exception of RRDS data sets. Idms-set-name can be 1 to 16 characters in length.

ERASE option is ERASE ALL/ERASE PERMANENT/ERASE SELECTIVE/ERASE RECORD/DISCONNECT

Identifies the type of ERASE that CA IDMS VSAM Transparency will perform when processing VSAM ERASE requests. The default is ERASE ALL.