UNDOINFORMATION 
The system table SYSINFO.UNDOINFORMATION contains information about all current undo files.
Structure
TRANSACTIONID |
FIXED(15) |
Identification of the transaction |
PARTITIONID |
FIXED(5) |
Identification of the partition |
UNDOROOT |
FIXED(10) |
First page in the chain of undo pages |
UNDOLAST |
FIXED(10) |
Last page in the chain of undo pages |
UNDOPAGECOUNT |
FIXED(10) |
Number of used undo pages |