The Delete Duplicate Records command deletes duplicate records in a
named file based on a series of key fields. By default, only a
listing is output with what would occur if ACTION(*DELETE) was
specified. When *DELETE is specified, the first duplicate record of
a group is retained and the others are deleted.
You must have all rights to the file to use DLTDUPRCD.
An exclusive lock (*EXCL) is requested on the member when running
DLTDUPRCD with ACTION(*DELETE).
The named file is sorted to a temporary file in QTEMP. If *DELETE is
requested, the duplicates are deleted from the temporary file, and
then the temporary file is copied back to the named file using
MBROPT(*REPLACE).
A typical command would be:
DLTDUPRCD FILE(xxx) FIELD(FIELDA) PRTFLD(FIELDB)
Because the default of ACTION(*CHECK) was used, no records would be
deleted. A listing would be output of any duplicates found based on
FIELDA. The value of FIELDA would be listed along with the value of
FIELDB which is used to help identify the records.
If ACTION(*DELETE) had been specified, all but the first duplicate of
each group would be deleted. The same listing would be output with
an indication of what records were deleted.
Use with RTVDLTRCD TAA Tool
---------------------------
Because of the technique used by DLTDUPRCD, the records are not
deleted in the named file. Instead, the records are deleted from a
sorted copy and then the remaining records are copied back to the
named file using MBROPT(*REPLACE).
Consequently, there will not be any deleted records in the file upon
completion and RTVDLTRCD cannot be used.
For the best protection, you should make a backup of the file before
using DLTDUPRCD.
DLTDUPRCD escape messages you can monitor for
----------------------------------------------
None. Escape messages from based on functions will be re-sent.
Command parameters *CMD
------------------
FILE The qualified name of the file to be checked for
duplicate values. The library value defaults to
*LIBL. *CURLIB may also be used.
FIELD Up to 6 field names to be checked for duplicate
values. The file is sorted using the field names as
the sort fields. The field values are concatenated
together before checking for duplicates. Character
fields must be 50 characters or less. Variable
length fields are not supported. Decimal fields
must be 15 digits or less.
PRTFLD A list of up to 3 print fields that will be printed
along with the duplicate values to help identify the
duplicates. The default is *NONE meaning only the
duplicate values will be listed.
Character fields may be any length, but only the
first 50 bytes are listed. Decimal fields must be
15 digits or less.
MBR The member to be processed for duplicate values.
The default is *FIRST based on the create date.
*LAST may be specified to process the last member in
the file based on create date.
ACTION The type of action to be performed. *CHECK is the
default to output a listing describing what would be
deleted. No records are deleted.
*DELETE may be specified to delete duplicates. The
first duplicate of a group is retained. The other
duplicates are deleted. A listing occurs.
OUTPUT How to output the results. * is the default to
display the spooled file if the command is entered
interactively. The spooled file is deleted after it
is displayed.
If the command is entered in batch or *PRINT is
specified, the spooled file is output and retained.
Restrictions
------------
** For the fields specified for the FIELD parameter to determine
duplicates: a) Character fields must be 50 characters or less
and cannot be variable length b) Decimal fields must be 15
digits or less.
** The record length must be 9999 bytes or less.
Prerequisites
-------------
The following TAA Tools must be on your system:
CHKOBJ3 Check object 3
EDTVAR Edit variable
EDTVAR2 Edit variable 2
EXTLST Extract list
EXTLST2 Extract list 2
HLRMVMSG HLL Remove message
RSNLSTMSG Resend last message
RTVDBFA Retrieve data base file attributes
RTVFLDA Retrieve field attributes
RTVFLDARR Retrieve field array
RTVSYSVAL3 Retrieve system value 3
SNDCOMPMSG Send completion message
SNDESCINF Send escape information
SNDESCMSG Send escape message
SNDSTSMSG Send status message
SORTDBF Sort data base file
Implementation
--------------
None, the tool is ready to use.
Objects used by the tool
------------------------
Object Type Attribute Src member Src file
------ ---- --------- ---------- ----------
DLTDUPRCD *CMD TAADBKM QATTCMD
TAADBKMC *PGM CLP TAADBKMC QATTCL
TAADBKMR *PGM RPG TAADBKMR QATTRPG
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