How does sql server decides which transaction is first and which one is the last if both happen at the same time -


i have basic question transaction - if 2 transactions different sessions start @ same time, 1 transaction has wait till other finishes. 1 of acid properties. question how system decide transaction first 1 , 1 has wait both transactions happen @ exatly same time.

right, not possible determine since sql server internal. see when there 2 processes accessing same table, once process declared dead lock victim while other executes. choosing process dead lock victim taken care sql server. believe might consider milli seconds or micro seconds difference between 2 processes , set priority.

hope helps!


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