How to Use

INIT CXX/FXX/IXX/LXX/Data Area › INIT IXX (Format Index Area) › How to Use

How to Use

You can execute this command in either Single User or Multi-User mode. To format an Index Area, execute DBUTLTY using the following command format:

►►─ INIT AREA=IXX,DBID=n ─┬───────────────────────┬─┬────────────────┬────────►
                          └─ ,VERIFY= ─┬─ NO ◄ ─┬─┘ └─ BLKSIZE=size ─┘
                                       └─ YES ──┘

 ►─┬──────────────────────┬─┬───────────────┬─────────────────────────────────►◄
   └─ OLDEP= ─┬─ YES ◄ ─┬─┘ └─ IXXAREA=aaa ─┘
              └─ NO ────┘

Command

INIT: Invokes the function to format areas for CA Datacom/DB use.

Required Keywords

AREA=IXX

Identifies the area to be formatted as the Index.

,DBID=

Identifies the database.

Valid Entries:: DATACOM-ID of the database
Default Value:: (No default)

Optional Keywords

,VERIFY=

If you do not specify the VERIFY= option, or if you specify VERIFY=NO (the default), an INIT opens the data set for output, builds a new control block, and initializes the extents.

If you specify VERIFY=YES, an INIT opens the data set for update, reads and updates an existing control block, and initializes the extents.

Because a new control block is always built with VERIFY=NO, specifying VERIFY=YES when the INIT is not for a new data set brings several benefits, including the following:

Because an existing control block is read and updated instead of a new one being built, the data area history (in the control block) documenting activities such as backups and loads is not lost. Data area history information can be a valuable aid when troubleshooting various problems.
VERIFY=YES prevents the unintentional overlaying of important information because of a JCL error, such as writing over files in PRODuction status that should have been in TEST status, or the inadvertant overlaying of the Directory (CXX) or Log Area (LXX).

Note: Even with VERIFY=YES specified, the last extent and the number of extents is lost during an initialize.

Valid Entries:: YES or NO
Default Value:: NO

BLKSIZE=size

This optional keyword allows you to select a block size other than the default. BLKSIZE= can be used to specify an index block size of from 4096 bytes through 8192 bytes. The BLKSIZE= value remains in effect until the next initialization of the IXX. You must pick an optimal size for your device type, in a manner similar to how the data area block size is selected. See the description of BLKSIZE= in the table of required keywords, see How to Use.

We do not recommend changing the block size from the default. See Controlling the Index Block Size.

Note: An OPEN error occurs if an attempt is made to open a database that has an index block size larger than the index buffer size. See the information about the ixxbfrsize parameter of the SYSPOOL Multi-User startup option in the CA Datacom/DB Database and System Administration Guide.

Valid Entries:: 4096 through 8192
Default Value:: 4096 (or, for some device types, a little less)

OLDEP=

Refers to old entry points. When OLDEP=NO is specified, the DBNTRY entry point, designated as the primary entry point since the early 1980s, is the only entry point supported. For compatibility with prior versions, OLDEP=YES is the default, allowing the use of older entry points such as CBLDBMS and DATACOM. Those older entry points, however, use index blocks limited to a maximum of 255 entries. Specifying OLDEP=NO, to ensure that DBNTRY is used in Version 11.0, allows you to use index blocks that can hold a maximum of 8K entries. Therefore, if you want to use 8K index blocks, and for some performance enhancement, use OLDEP=NO.

Note: Do not initialize an index using the OLDEP= keyword until you are certain that the risk of needing to do a fallback to a prior version no longer exists. OLDEP= index initializations are not compatible with prior versions. If used in a prior version, an open error and a return code 43(43) NO VALID INDEX is received.

Alternately, if a program attempts using an old entry point with an index initialized as OLDEP=NO, the request fails with a return code 39(090) CANNOT PROCESS OLD REQUEST.

Valid Entries:: YES or NO
Default Value:: YES

IXXAREA=aaa

IXXAREA= is optional for databases that have a single Index Area IXX but, if specified, must be set as IXXAREA=IXX. IXXAREA= is required, however, for databases that have a Multi-Dataset Index and must be specified with one of the following: IXX, Inn (where nn can be 00 to 99), or *** where the *** (3 asterisks) means to initialize the IXX and then each additional index area in turn. The use of *** forces the same options for every area, including VERIFY=, BLKSIZE=, and OLDEP=.

Valid Entries:: IXX, I00 to I99, or ***
Default Value:: (No default)