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

DEFINE ALTERNATEINDEXRestriction: When FILE refers to more than one volume of the same devicetype, the DD statement that describes the volumes cannot be a concatenatedDD statement.FREESPACE(CI-percent[ CA-percent]|0 0)Designates the amount of empty space left after any primary or secondaryallocation and any split of control intervals (CI-percent) and control areas(CA-percent) when the alternate index is built (see Chapter 8, “BLDINDEX,” onpage 91). The empty space in the control interval and control area is availablefor data records that are updated and inserted after the alternate index isinitially built. The amounts are specified as percentages. CI-percent translatesinto a number of bytes that is either equal to, or slightly less than, thepercentage value of CI-percent. CA-percent translates into a number of controlintervals that is either equal to, or less than, the percentage of CA-percent.The percentages must be equal to, or less than, 100. When you use 100% offree space, one data record is placed in the first control interval of each controlarea when the alternate index is built.Abbreviation: FSPCIMBED|NOIMBEDIMBED|NOIMBED is no longer supported; if it is specified, VSAM ignores it,and no message is issued.KEYRANGES((lowkey highkey)[(lowkey highkey)...])KEYRANGE is no longer supported; If you specify this parameter, VSAMignores it, and no message is issued.KEYS(length offset|64 0)Describes the alternate-key field in the base cluster’s data record.The key field of an alternate index is called an alternate key. The data record’salternate key can overlap or be contained entirely within another (alternate orprime) key field.The length plus offset cannot be greater than the length of the base cluster’sdata record.When the base cluster’s data record spans control intervals, the record’salternate-key field is within the record’s first segment (that is, in the firstcontrol interval).length offsetGives the length of the alternate key, in bytes, and its displacement fromthe beginning of the base cluster’s data record, in bytes.MODEL(entryname[ catname])Uses existing entry as a model for the entry being defined or re-cataloged.DATACLASS, MANAGEMENTCLASS, and STORAGECLASS cannot bemodeled. See “Specifying Attribute Selection Order” on page 14 forinformation on how the system selects modeled attributes.You can use an existing alternate index’s entry as a model for the attributes ofthe alternate index being defined. For details about how a model is used, seez/OS DFSMS: Managing Catalogs.You can use some attributes of the model and override others by definingthem in the cluster or component. If you do not want to add or change anyattributes, use only the entry type of the model (alternate index, data, or index)and the name of the entry to be defined.134 z/OS V1R6.0 DFSMS Access Method Services for Catalogs