Rollback:
-----------



Recovery:
-----------

ARIES series of algorithms:
------------------------------

-> Analysis
-> REDO
-> UNDO


Consistent state:

-> Data pages modified by commited transactions are recorded
-> Data pages modified by uncommitted transactions are rolled back


Assume:

-> No force
-> Steal





Log
---------


101  T1 update P1   - 
102  T2 update P3   -
103  T3 update P4   -
104  T1 update P2   101
105  T2 update P5   102
106  T4 update P6   - 
107  T1 update P1   104
108  T2 commit      105
109  T1 commit      107
110  T3 update P1   103
111  T4 abort       106
112  UNDO 106       -
113  T5 update P3   -
114  T3 update P6   110
115  T5 update P2   113


Data pages
-------------

P1  110
P2  104
P3  113
P4  103
P5   91
P6  111




---  BEGIN CHECKPOINT
---  TT   T3 103  T4 106
---  DPT  P3 102 P5 105
---  END   CHECKPOINT
110  T3 update P1   103
111  T4 abort       106
112  UNDO 106       -
113  T5 update P3   -
114  T3 update P6   110
115  T5 update P2   113