TurboIMAGE/XL Database Management System Reference Manual MPE/iX V6.5 (30391-90011)

Appendix E 649
TurboIMAGE/XL Log Record Formats
E TurboIMAGE/XL Log Record Formats
This appendix shows the TurboIMAGE/XL log record formats for the DBBEGIN, DBCLOSE,
DBDELETE, DBEND, DBMEMO, DBOPEN, DBPUT, DBUPDATE, DBXBEGIN, DBXEND, and
DBXUNDO intrinsics. Note that the recovery flag will always be zero in the log file records.
This flag is used during recovery if user recovery files are created.
NOTE All TurboIMAGE/XL records are contained within MPE/iX "WRITELOG"
records. Consequently, all information contained in the header portion of each
WRITELOG record is available, in addition to the information provided by
TurboIMAGE/XL.
DBBEGIN
HALFWORD(0-8) - MPE WRITELOG RECORD
HALFWORD(9) - TURBOIMAGE/XL LOG RECORD LENGTH
HALFWORD(10) - DBBEGIN LOG RECORD CODE ("BE")
HALFWORD(11) - DATA SEGMENT NUMBER
HALFWORD(12) - RECOVERY FLAG ("NO"-FAILED,"OK"-RECOVERED)
OR MULTIPLE DATABASE TRANSACTION SEQUENCE ID
HALFWORD(13) - TRANSACTION NUMBER (1 WORD)
HALFWORD(15) - LENGTH OF USER BUFFER
HALFWORD(16) - START OF USER BUFFER
DBBEGIN Mode 4 (MDBXBEGIN)
HALFWORD(0-8) - MPE WRITELOG RECORD
HALFWORD(9) - TURBOIMAGE/XL LOG RECORD LENGTH
HALFWORD(10) - MDBXBEGIN LOG RECORD CODE ("TB")
HALFWORD(11) - NOT USED
HALFWORD(12) - SEQUENCE ID
BITS 0-3 = RESERVED
BITS 4-9 = SEQUENCE NUMBER
BITS 10-15 = TOTAL NUMBER OF DBBEGIN/DBEND
LOG RECORDS IN THE SEQUENCE
HALFWORD(13-14) - TRANSACTION ID
HALFWORD(15) - LENGTH OF USER BUFFER
HALFWORD(16) - START OF USER BUFFER
HALFWORD(17) - NUMBER OF BASE IDs INVOLVED IN MDBX
HALFWORD(18) - DATA SEGMENT NUMBER OF FIRST BASE ID
HALFWORD(19-20) - TRANSACTION NUMBER FOR 1ST BASE ID
HALFWORD(21) - DATA SEGMENT NUMBER OF SECOND BASE ID
HALFWORD(22-23) - TRANSACTION NUMBER FOR 2ND BASE ID