CICS File HandlingCICS RELEASE Statement CICS FILE DELETE
CICS supports only VSAM and BDAM files.
All the files used in CICS application, should be registered in FCT with the complete attributes.
CICS commands will use the FCT entry for performing the operations on the file.
The files which are not declared in FCT table will not be recognized by the CICS.
In CICS, the entries in FILE SECTION or DATA DIVISION entries are not required because the file is declared in FCT and the data about the file is available to all.
Once the file declared in the FCT, the file operations like OPEN, CLOSE, SHARE, ENABLED, DISABLED can be verify by the user by using CEMT command and user can able to override the same by using the same CEMT transaction.
CICS Supports sequential/Random reading of Key sequential datasets.
The CICS commands for file handling can be discussed below based on the types of files.
- Random Reading
- Sequential Reading.
Delete a record from a file.
The file can be VSAM KSDS, VSAM RRDS and data tables only.
The DELETE command deletes a record from a file on a KSDS.
The DELETE command can also deletes the records from data table, or an RRDS.
DELETE can be explained in detail here.
Read a record from a file.
READ command used to read file and retrieve the data based on the key passed.
The file can be local file or file from remote region.
For both UPDATE and non-UPDATE commands, RIDFLD option is required to identify the record to be retrieved.
READ can be explained in detail here.
Read next record during a browse of a file.
READNEXT used repeatedly to read records in sequential order from a file.
The file can be on local or remote system.
The series of sequential read commands is known as a browse of the file.
READNEXT can be explained in detail here.
Read previous record during a file browse
REDPREV is applicable for VSAM and data tables only.
READPREV can be used repeatedly to read records in reverse sequential order.
The VSAM file can be on a local or a remote system.
READPREV can be explained in detail here.
End the browse of a file.
ENDBR ends a browse on a file.
The file can be on a local or a remote CICS region.
For some cases, ENDBR command before using READ UPDATE to avoid self deadlock abends.
ENDBR can be explained in detail here.
CICS RELEASE Statement CICS FILE DELETE