Hi-
 

 Is there a way I can draw a diagram and match it to my input in isql?
 

 I am trying to set the default transaction in each of my isql clients that are 
open in separate windows.
 In each isql I type: set transaction wait isolation level read committed.
 

 I tried to make a chart like this to document what I am doing.
 isql-1                                         isql-2

 __________________________________________
 980- tid                                    |    982

 _________________________________________________
 

 update                                |   update/wait
 ___________________________________________________
 

 commit (no error)                                

 ___________________________________________________
 new tid - 984                         |     982
 ___________________________________________________
 update/wait                           |  update
 ____________________________________________________

                                            |  commit (error)
 ___________________________________________________
 984                                      |   986 new tid
 

 on p. 196 of volume 2 it says:
 

 with no record_version - "it blocks this transaction from writing a new 
version of the row...."
 with wait :  (allowable if - its own tid is newer than the other transactions 
tid)
 

 I don't want to retype the exact wording out of helen's book because of 
copyright.
 

 my diagram and the data in it don't make sense to me. on wait, if my tid is 
newer (higher #)

 than the other tid, why do I get the deadlock error?
 

 I hope there is an easy way for someone to demonstrate this to me.
 I wish I had tried this experiment with trying to figure out transactions a 
long
 time ago. I didn't realize I'd get this stuck.
 

 Please assist- 

 I am really lost on this one. Not sure what I am missing.

 thanks (3rdshiftcoder)

 

 

 

 

 

 

 

 

 

 

 

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