FILELOAD command

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Summary

Privileges
File manager (as User 0 only)
Function
Starts a File Load (single-step) program

Syntax

FILELOAD k, n, m [,[s1] [,[s2] [,[s3] [,[s4] [,v1]]]]]

Where:

k The maximum number of records to be loaded into the Model 204 file.
n The maximum number of times that the statements in the File Load program are to be executed.
m The number of input records to skip before starting the load process.
s1 The amount of memory that the sort uses for sorting the deferred update index records produced by the File Load program. If s1 is omitted or is not a positive integer, a default value of 50000 bytes (64K for z/VM) is used for the sort work space.

It is important to increase s1 for large sorts. The s1 parameter should be made as large as practical, especially for sorts involving many records.

s2 The amount of memory to be used for sorting the deferred update FRV index records. It defaults to 50000 bytes (64K for z/VM) if s2 is omitted or is not a positive integer. For 3380 disk drives, the minimum values for s1 and s2 are 64000 bytes.
s3 The amount of memory to be allocated for the two buffers used to pass data from Model 204 to the sorts. This parameter specifies the combined size of the two buffers. The core specified in s3 is evenly divided between the two buffers, and s3 defaults to 8000 bytes.

The minimum value accepted is 48 bytes, but such a small size is not recommended. Larger sizes might produce a noticeable performance improvement. An increase in s1 normally has a greater effect on performance than a corresponding increase in s31.

s4 The amount of memory that is allocated for the two buffers used to pass data from the sorts to Model 204. s4 is ordinarily equal in size to s3, and it is set equal to s3 by default.
vl The maximum sort record length in variable-length record sorts.

The vl parameter is required when ORDERED fields are updated by the File Load program. For efficiency, the vl option should not be present when ORDERED fields are not updated. For more information on the vl option, see Setting the variable-length sort parameter (vl).

Syntax notes

  • FILELOAD must be issued in file context (that is, the current default must be a file, not a group).
  • Specify commas to hold places for missing arguments. When an argument is missing, the default value (if any) is used. (See the examples below.)

Example

OPEN CENSUS FILELOAD -1, -1, 1,102400, 100 G HOUSEHOLD ID=1,5,X'804C' SEX=6,1,X'0410' UNKNOWN=MALE=FEMALE= PLACE SIZE=9,2,X'0410' UNKNOWN= FARM=RURAL=URBAN=5000=10000= 25000=50000=100000=250000= 500000=1000000= OVER 1000000= END

In the following example, arguments s1 and s4 are missing (default values are used):

FILELOAD -1, -1, 1,,1000, 1000

Usage notes

  • The FILELOAD command invokes the File Load (FLOD) utility. It is used when a single-step File Load procedure is being performed.

    The FLOD command is used to invoke a multistep File Load procedure.

    Note: For a site that is authorized for Fast/Reload, the FLOD and FILELOAD commands are syntactically unchanged but invoke Fast/Reload, which compiles and executes the FLOD and FILELOAD programs.

  • The FILELOAD command is not supported under z/VSE.
  • FILELOAD signals the start of a File Load program, which consists of special statements that load data from a sequential file into a Model 204 file.

    To make the File Load program execute efficiently, set the MAXBUF parameter to a value between 5 and 10. Also, make the value of the s1 attribute as large as is practical. The exceptions to these guidelines are:

    • FILELOADs of hash-order files that do not use the sort exit M204HASH
    • FILELOADs that extensively use the locate statement
  • The Model 204 FILELOAD exit feature allows for modification of the record image upon which the FILELOAD (or FILELOADX) command acts. With the FILELOAD exit feature, you can create a COBOL or Assembler program to modify the image records. The FILELOAD exit feature enables the use of more than one input file for FILELOAD processing. The FILELOAD exit is modeled on SORT exits, similar to the E15 sort exit. The FILELOAD exit feature is documented in FLOD exits.
  • When it processes FILELOAD, Model 204 ends any update unit in progress and begins a non-backoutable update unit. For more information about Model 204 update units, see Update units and transactions.
  • For more information about the FILELOAD command, the File Load utility, the File Load statements, and input data set requirements, see Category:File loading and reorganization.