z/OS V1R6.0 DFSMS Access Method Services for Catalogs

ALTER||||||||||||||||should manage. Use this parameter to alter the data component of a catalog.The STRNO setting is ignored when the data set is opened for RLS orDFSMStvs.numberIs the number of concurrent requests VSAM must manage. The minimumnumber is 2, the maximum is 255.TO(date)|FOR(days)Specifies the retention period for the entry being altered.You cannot use these parameters for the data or index components of clustersor alternate indexes. For catalogs, you must use the data component name. Theexpiration date in the catalog is updated, and, for SMS-managed data sets, theexpiration date in the format-1 DSCB is changed. Enter a LISTCAT commandto see the correct expiration date.The MANAGEMENTCLASS maximum retention period, if specified, limits theretention period specified by this parameter.TO(date)Specifies the earliest date that a command without the PURGE parametercan delete an entry. Specify the expiration date in the form yyyyddd, whereyyyy is a four-digit year (to a maximum of 2155) and ddd is the three-digitday of the year from 001 through 365 (for non-leap years) or 366 (for leapyears).The following four values are ″never-expire″ dates: 99365, 99366, 1999365,and 1999366. Specifying a ″never-expire″ date means that the PURGEparameter will always be required to delete an entry. For relatedinformation, see the ″EXPDT Parameter″ section of z/OS MVS JCL Reference,SA22-7597.Notes:1. Any dates with two-digit years (other than 99365 or 99366) will betreated as pre-2000 dates. (See note 2.)2. Specifying the current date or a prior date as the expiration date willmake an entry immediately eligible for deletion.FOR(days)Is used to choose the number of days to keep the entry. The maximumnumber is 9999. If the number is 0 through 9998, the entry is retained forthe number of days indicated; if the number is 9999, the entry is retainedindefinitely.TYPE(LINEAR)Specifies that the VSAM data set type of an entry-sequenced data set (ESDS) isto be changed to linear. The contents of the data set are not modified. Only anESDS with a CI size of 4096 is eligible to be a linear data set. A linear data set’stype cannot be changed. After you have changed an ESDS set to a linear dataset, the data set must remain a linear data set; you cannot change it back intoan ESDS.LINEARChanges the VSAM data type ESDS to a linear data set (LDS).Abbreviation: LINUNIQUEKEY|NONUNIQUEKEYSpecifies whether the alternate key value can be found in more than one of thebase cluster’s data records.Chapter 5. ALTER 71