Accesses are used to retrieve records from direct, ordered, or random data sets. An Access functions like a set, but there is no physical file associated with it. Instead, the Access defines the actual physical ordering of the records in the data set. Any record in the data set can be retrieved using an Access.
Only one Access can be declared for each direct, ordered, or random data set. Accesses must not be declared for other types of data sets.
The following diagrams illustrate the syntax for using Accesses:
Access Declaration
──<Access name>─┬───────────┬─ ACCESS ─┬──────┬─<data set name>────────►
└─<comment>─┘ └─ TO ─┘
►─<key clause>─┬──────────────┬─┬──────────────────────────┬───────────┤
└─<duplicates>─┘ └─<Access physical option>─┘<key clause>
── KEY ─┬──────┬─┬─<key item>─────────────┬────────────────────────────┤
└─ IS ─┘ │ ┌◄──── , ────┐ │
└─ ( ─┴─<key item>─┴─ ) ─┘<key item>
──┬─<field item name>───┬─┬───────────────────────────┬────────────────┤
├─<group item name>───┤ ├─ ASCENDING ───────────────┤
├─<numeric item name>─┤ └─ DESCENDING ──────────────┘
├─<real item name>────┤
├─<alpha item name>───┤
└─<RSN item name>─────┘
<duplicates>
──┬─────┬─┬─ DUPLICATES ─┬─────────┬───────────────────────────────────┤
└─ , ─┘ │ ├─ FIRST ─┤
│ └─ LAST ──┤
└─ NO DUPLICATES ────────┘
<Access physical option>
┌◄──────────────────────────── , ──────────────────────────────┐
│ │
──┴─┬─/1\─ MODULUS ─────────── <unsigned integer ──────────────┬─┴─────┤
└─/1\──SECTIONS ( <section specification list> ) ──────────┘<section specification list>
┌◄──────────────────────────── ; ──────────────────────────────┐ │ │ ──┴────── <section key specification> ───────────────────────────┴────┤
<section key specification>
┌◄──────────────────────────── ; ──────────────────────────────┐ │ │ ──┴────── <key item> = <key value> ──────────────────────────────┴────┤
The following text explains the elements of the syntax diagram.
