The Replace Physical File command allows you to make DDS changes and
then specify the RPLPF command to replace an existing physical file
and all dependent logicals.
RPLPF will operate successfully on:
- A physical file with a single member
- A physical file with multiple members
- A physical file with no members
- A physical file with no dependent logical files
- A physical file with dependent logical files.
The intent of RPLPF is to allow you to just change the DDS for the
file and then issue a simple command. The following would be used
when simple changes occur such adding or dropping a field, changing
the length of a field, or a change to DDS functions such as COLHDG or
TEXT (a different CPYF option is required when the name of a field is
changed in the DDS).
RPLPF FILE(FILEX) CPYF(*MAPDROP)
Any existing data in the file is copied (by default) to the new file
using CPYF with FMTOPT(*MAP *DROP). Any dependent logical files will
also be re-created.
No dependent programs are re-created. If you need to re-create
dependent programs, see the TAA Tool RBLDBF.
RPLPF will do the following:
** Extract the existing attributes of the file (e.g. MAINT) and
use them to re-create the file.
** Copy the existing authorities to the new file.
** Re-create any members using their existing attributes (e.g.
the SHARE parameter).
** Copy (by default) any existing data from the corresponding
members to the new members using FMTOPT(*MAP *DROP). This
allows you to add new fields to the format, change existing
attributes, or delete fields (CPYF restricts mapping from a
character to decimal field or vice versa).
** Restart physical file journaling if needed.
** Restart access path journaling if needed.
** Determine if any trigger programs exist and if so re-specify
them on the new file.
** Determine the dependent logical files and re-create them using
the TAA Tool RPLLF.
To change a field name requires that the record length of the old
version and the new version remain the same. Thus if you are
changing a field name, you cannot add/drop fields or change field
lengths at the same time (you can change DDS functions that do not
impact the record length such as COLHDG or TEXT). A typical command
would be:
RPLPF FILE(FILEX) CPYF(*RNMFLD)
Note that if you are changing a field name, any use of the same field
name in logical file DDS should also be changed before using RPLPF.
DEPLFP file in QTEMP
--------------------
For each logical that is created, a record is added to the DEPLFP
file in QTEMP. If no LFs exist, the file will not exist.
The model file is TAADBFZP with a format name of LFRCD.
Command parameters *CMD
------------------
FILE The qualified file name of the physical file. The
library value defaults to *LIBL. *CURLIB may also
be specified.
CPYF The type of CPYF command that should be used.
*MAPDROP should be specified when you are adding a
new field, dropping a field, changing the length of
a field, or changing a DDS keyword such as COLHDG or
TEXT. CPYF is used with FMTOPT(*MAP *DROP).
*RNMFLD should be used when you are renaming a
field. When *RNMFLD is used, the length of the old
version and the new version must be the same. CPYF
is used with FMTOPT(*NOCHK). Therefore, you cannot
rename a field and also add/drop fields or change
lengths at the same time. You can use *RNMFLD and
also make a change to a DDS keyword that will not
impact the length such as COLHDG. Note that if you
use *RNMFLD, the use of the same field name in
dependent logical file DDS should be changed before
using RPLPF.
*NO may be specified to not copy any of the data.
This will recreate the data base network, but none
of the data will be copied.
*YES is the previous default used and is mapped to
*MAPDROP.
DLTSPLF Whether the spooled file created by the CRTPF
command should be deleted. The default is *YES
which will cause a deletion if the data base network
is successfully replaced. If the file is not
created successfully, or the member is not added
properly, or any dependent logical files or their
members are not properly re-created, the spooled
file will still exist. *NO may be specified to
always retain the spooled file.
SRCARCLIB Whether a source archive may hold the source for the
files to be re-created. The default is *NONE. This
refers to the TAA Tool SRCARC which allows the
removal of source from the source files.
If an archive library is named and the source does
not exist in the source member used to originally
create the object, the source data will attempt to
be copied out of the archive to the original member.
If successfully copied from the archive, the source
is used to create the file and then removed.
OWNER Who the owner of the file should be. The default is
*CURRENT for the user of the command. If any
logical files are created, they will also be owned
by the current user.
*SAME may be specified to retain the same owner.
*SAME may only be specified when the current user
has *ALLOBJ special authority. If any logical files
are created, they will also retain their current
ownership.
Sequence of processing
----------------------
In order to replace a physical file with dependent logicals, the
following sequence of events occurs:
** The file is accessed to determine that it is a physical file,
the DDS exists, and the file is not is use.
** The DDS for the existing file is used to recreate a file of
the same name in QTEMP. The same file name cannot exist prior
in QTEMP. If the file cannot be created, the program
abnormally terminates and the existing data base network is
still intact. The file will not exist in QTEMP.
** If the file is created successfully, the authorizations from
the existing file are copied to the new file and journaling is
restarted if needed.
** If the physical file is keyed, a sub program is called to
determine if the access path of the existing file is
journaled. If so, access path journaling is restarted.
** The member list for the existing file is accessed and each
member is re-created using the attributes of the existing
member.
The members are accessed using DSPFD *MBRLIST. This causes an
alphabetical sequence of member names to be name and the new
members are created in that order. This may not be the
sequence of the existing file.
** If records exist in the old member and if CPYF(*MAPDROP) was
specified, the old member data is copied to the new member
with FMTOPT(*MAP *DROP). If CPYF(*RNMFLD) was specified, the
old member data is copied using FMTOPT(*NOCHK).
** Any dependent logical files are determined.
** The old physical file is renamed to TAATMPRPL in the existing
library. The file name TAATMPRPL must not exist in the same
library. Any dependent logical files now point to TAATMPRPL.
This allows the TAA Tool RPLLF to be used where the old files
still exist and the new files will be built over the new
physical file.
** The new file in QTEMP is moved to the original library. No
logical files exist over the new file at this point.
** Any dependent logical files are re-created using the TAA Tool
RPLLF.
** If a logical file cannot be re-created over the new physical,
at attempt will be made to delete the file.
** When all logical files have been processed and there are no
more dependent files based on the TAATMPRPL file. The
TAATMPRPL file is deleted.
** If no errors occurred in either the create of the physical
file, the adding of physical members, the creation of logical
files, and the adding of logical members, the spooled file for
the CRTPF command is deleted if DLTSPLF(*YES) was specified.
Recovery
--------
In most cases, the RPLPF command will complete normally. However,
there are several reasons a failure may occur and you may need to
recover.
** If the new physical file cannot be created in QTEMP, the data
base network will still be intact.
** The new physical file will be created in QTEMP, but the
program may not be able to continue past that point. The old
physical still exists at that time and you will need to
determine the problem and then delete the QTEMP version.
** If the physical file can be re-created and the members added,
the old physical file will be renamed to TAATMPRPL and the new
file is moved from QTEMP.
If dependent logical files exist, there is a possibility that
they cannot be replaced and therefore the TAATMPRPL file will
still exist (It cannot be deleted because dependent files
still exist over it). For example, this would occur if a
logical file was in use, the user was not authorized to delete
the file, no source exists, etc.
An escape message will describe the problem. You should use DSPDBR
against the TAATMPRPL file to determine what logicals still exist.
These should be manually deleted along with TAATMPRPL. You should
then manually re-create any of the logical files that could not be
replaced. The new physical file will be correct at that point.
Restrictions
------------
The physical file cannot be replaced if it is in use.
Once the command begins, you should let it finish without
interrupting it (e.g. System Request - ENDRQS) to allow the proper
cleanup.
You should not use RPLPF more than once at the same time for the same
library. This is due to the renaming convention used for the
TAATMPRPL file name.
If multiple members exist, the sequence in which the members are
added to the new file may differ.
Prerequisites
-------------
The following TAA Tools must be on your system:
ALCTMPMBR Allocate temporary member
ALCDBF Allocate data base file
CHKAPOST Check apostrophes
EDTVAR Edit variable
RPLLF Replace logical file
RTVDBFA Retrieve data base file attributes
RTVPFA Retrieve physical file attributes
SNDCOMPMSG Send completion message
SNDESCMSG Send escape message
SNDSTSMSG Send status message
SRCARC Source archive
Implementation
--------------
None, the tool is ready to use.
Objects used by the tool
------------------------
Object Type Attribute Src member Src file
------ ---- --------- ---------- ----------
RPLPF *CMD TAADBFZ QATTCMD
TAADBFZC *PGM CLP TAADBFZC QATTCL
TAADBFZC2 *PGM CLP TAADBFZC2 QATTCL
TAADBFZC3 *PGM CLP TAADBFZC3 QATTCL
TAADBFZC4 *PGM CLP TAADBFZC4 QATTCL
TAADBFZC5 *PGM CLP TAADBFZC5 QATTCL
Structure
---------
RPLPF
TAADBFZC CPP and main processing program
Does CRTPF
TAADBFZC2 Does RPLLF for each dependent file
TAADBFZR2 Writes records to DEPLFP in QTEMP
TAADBFZC3 Checks access path journaling
TAADBFZC4 Checks authority to dependent LFs
TAADBFZC5 Re-specifies any trigger programs
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