Disk or pack files are divided in areas. Areas are allocated only as they are needed; thus, a potentially large file can be small initially and grow as necessary. The user can control the amount of disk space allocated to a file by using the AREAS and AREASIZE (or AREALENGTH) options. The maximum file size is 2**28 – 1 (268435455) segments. The maximum AREASIZE is 143,165,576 segments. LIMITERROR 1 occurs when a program stores more records than the maximum file size. To avoid this problem, run garbage collection to consolidate deleted space or reorganize the structure to have more sections.
For a sectioned direct data set, the following information applies:
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The file size per section is by default derived from the size of the largest section in the Access based on the difference between consecutive section bounds. This default file size per section can be overridden by specifying the full file size per section using AREAS, AREASIZE, and BLOCKSIZE if AREASIZE is given in blocks.
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The embedded structures (data sets, sets, and subsets) of a sectioned direct data set must have their file sizes fully specified using AREAS, AREASIZE, and BLOCKSIZE if AREASIZE is given in blocks.
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The index sets and subsets of a sectioned direct data set must have their file sizes fully specified using AREAS, AREASIZE, and BLOCKSIZE if AREASIZE is given in blocks.
The AREAS option specifies the number of areas to be assigned to a file. The maximum value allowed for the AREAS option is the result of 1000 –N, where N is the number of areas allocated for the system. Because the FLEXIBLE attribute is TRUE for sets and subsets, the actual number of areas that the set or subset contains can exceed the value specified by the user.
The user can specify the length of an area using the AREASIZE option. Area size can be specified in units of segments, tables, blocks, entries, or bytes. The tables unit is assumed by default.
If neither areas nor area size is declared, the system automatically computes values for them based upon the population and table size of the set or subset.
For index random sets and subsets, the default areas and area size values are large enough to contain the entire population despite an uneven distribution of records among the basic blocks.
The system always allocates extra disk areas for each data set, set, or subset. These system-allocated areas are provided in addition to the user-allocated areas that are specified explicitly or computed implicitly.
For sets or subsets, the system allocates one system area.
A syntax error is returned if the combination of system and user areas exceeds 1000 areas.
