18.2 Determining the size of a HiRDB file system area (pdfmkfs -n command)

Use the pdfmkfs command's -n option to specify the size of a HiRDB file system area in which a work table file is created.

The following formula is used to obtain the size of a HiRDB file system area in which work table files are to be created.

Formula
Size of HiRDB file system area (bytes) = A + B
A
Size of a work table file to be used by an SQL statement. For details about how to obtain this value, see 18.2.1 Size of a work table file used by an SQL statement.
B
Size of a work table file used by the database load utility (pdload), database reorganization utility (pdrorg), and rebalancing utility (pdrbal). For details about how to obtain this value, see 18.2.2 Size of a work table file used by a utility.

If you do not execute an SQL statement that uses a work table file concurrently with a utility that also uses a work table file, specify either A or B, whichever is larger, as the size of the HiRDB file system area.

Notes
If the size of the HiRDB file system area obtained with this formula is too large for one HiRDB file system area, initialize multiple HiRDB file system areas with the pdfmkfs command and specify the pdwork operand in the HiRDB system definition. In this case, note the following:
  • Set the size of each HiRDB file system area to the same value.
  • Make the size of each HiRDB file system area larger than the size of a work table (for storing column information).
  • If you divide a HiRDB file system area into too many segments, unused area is distributed among multiple HiRDB file system areas, and a shortage of space may occur because the space is not used efficiently.
  • If the size of a single work table file exceeds 2 gigabytes, specify Y or nothing in the pd_large_file_use operand and create a HiRDB file system area. A single work table file cannot be partitioned among multiple HiRDB file system areas.
Organization of this section
18.2.1 Size of a work table file used by an SQL statement
18.2.2 Size of a work table file used by a utility