Changed data log record format

The changed data log record contains fields that describe the first and last log records written for the call, the user ID for the call, the data element that is being logged, and other information regarding the log record.

The following table lists the record formats for changed data log records.

Table 1. Format for changed data log records
Field name Data type Field description
FLAG_1 XL1 Flag 1: Bit definitions follow:
LAST_RECORD X'80' The last log record written for this call. If this bit is not on, the remaining data for this DL/I call is in the log records that follow.
FIRST_RECORD X'40' The first log record written for this call. If this bit is not on, the data logged at LOG_DATA_OFFSET is the data that would not fit in the preceding record.
FIRST_CALL X'20' The first log record written for this unit-of-recovery, so LOG_INQY_DATA is present in this log record. (FIRST_RECORD is on.)
  X'10' Reserved for future use.
  X'08' Reserved for future use.
ERROR_LOG X'04' This log record is not complete because there was an error during the processing of the log records for this call. Data for the call might not have been logged.
DBLEWORD_SEQNUM X'02' The log sequence number is a doubleword.
STCK_AT_END X'01' Store clock at end of the log record.
FLAG_2 XL1 Flag 2: Bit definitions follow:
V11_9904_FORMAT X'80' The CAPD_DATA blocks in this log record contain SEGMENT_RBA_64 and SEGMENT_RBA_64H.
V11_9904_PARTNM X'40' Partition name in the X'9904' log record.
V13_9904_DBVER X'20' The database version number is logged in this X'9904' log record.
V13_9904_POSDATA X'10' Positioning data is captured in this X'9904' log record.
LOG_DATA_OFFSET H The offset in the log record where the DCAP_DATA elements start. When FIRST_RECORD is not on (indicating a split log record), this field is the offset to the continuation of the data from the previous log record.
COMPR_ALGORITHM XL1 The z/OS® compression algorithm used to compress DCAP_DATA.
  XL1 Reserved for future use.
LOCK_SEQ_NUM CL6 The IRLM lock sequence number used when IRLM SCOPE=GLOBAL used for block-level data sharing.
LOG_INQY_DATA   The following LOG_INQY_DATA fields are logged when FIRST_CALL is on.
PSBNAME CL8 The application PSB name.
TRANNAME CL8 The application transaction name.
USERID CL8 The user ID for the call. For a batch job, if the JOB statement has the USER= keyword, the USERID is the RACF® ID. For an online application, the USERID is either PSBNAME or RACFID.
RACF ID CL8 The value from the USER= keyword from the JOB statement.
RACFID or PSB name CL8 The value for online applications.
DCAP_DATA CL0 The data element being logged.