DB2

Ask/Clarify the questions on EASYTRIEVE

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SUBHANI
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Joined: Tue Jun 07, 2011 5:49 pm
Location: chennai

DB2

Post by SUBHANI » Wed Jun 08, 2011 9:29 am

can you please anybody explain about dead lock.
subhani

DikDude
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Post by DikDude » Wed Jul 27, 2011 6:43 am

Deadlock is not related to Easytrieve. . . Deadlock is a situation that happens when 2 processes attempt to read the same 2 database rows at the same time for update, but not in the same order.

Process 1 holds rowA, process 2 holds rowB and then one of the processes tries to read the row held by the other process. This introduces a wait - no real problem so far other than the wait time. NOW, when the other process tries to read the "other" row, the deadlock condition is raised and the process causing the deadlock is terminated.

For a more verbose explanation, suggest you look on the web or search for "fatal embrace". This happens on many database systems and is most often corrected by changing the code to lock rows consistently.
Have a good one

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