File Management - IBM

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Existing
Records
Added
Records
FILEDB2
Key
9
54
24
2
3
4
5
Relative
Record
Number
FILEDB2
Key
Keyed Access
View of To-File
There are several ways to select records for copying . One method is selection by
relative record number. (See “Selecting records by relative record numbers
(FROMRCD and TORCD Parameters)” on page 93.) Using the preceding example,
if you selected records to copy to a third file from FILEDB2 by relative record
number, from number 3 through 5, you would copy the records with a key value
of 24, 2, and 3, not 4, 5, and 9.
Specifying *UPDADD when copying files
1
2
3
4
5
6
7
Keyed Database
To-File in Arrival
Sequence
2
3
4
5
9
24
54
RV2H081-0
When you specify *UPDADD on the CPYF command, a from-file key value builds
before the from-file record moves into the to-file. The from-file builds this key
value by using the key specifications of the to-file. Before the key value is built, the
system performs any necessary field or data mapping, data conversion, or record
selection. The system checks the to-file to see if this key value already exists in it
(duplicate key of the from-file data). If the key value does exist in the to-file,the
from-file record that contains the key value updates that to-file record.
The following apply if you specify MBROPT(*UPDADD) on the CPYF command:
v The to-file must be a local database physical file that contains a primary or
unique key.
v You may not specify CRTFILE(*YES). The to-file must exist before you run CPYF.
v CPYF cannot copy from multiple formats.
v Detected duplicate keys are not skipped but updated with the new from-file
record value. Duplicate key errors (CPF5026) are not included as ERRLVL errors.
v CPF5027 will be included as an ERRLVL error. This error can occur if another
process has a record that is locked. To avoid this error, you may want to
pre-allocate the to-file within your job before performing the CPYF. You can use
the WAITRCD parameter on the CRTPF and CHGPF commands to limit the
length of time that the commands spend waiting for a record lock to be released
in the to-file.
v All existing FMTOPT values are allowed. However, when using
MBROPT(*UPDADD), take care to avoid updating records that you do not want
to update. Also avoid updating the same record multiple times when it is not
desired.
v Nulls are not used in determining duplicate key values if FMTOPT(*NOCHK) is
specified or if the from-file is a device file.
v You must have the minimum following authorities to the to-file:
Chapter 4. Copying files 87