concurrency - 2 Phase Locking and Deadlocks in DBMS -


hi people of stack overflow.

i have question regarding functionality of 2pl , deadlocks. don't know why hard me understand, i've tried making pseudo sequence diagram ease understanding.

pseudo sequence diagram of 2pl

is understanding of 2pl correct here? i'm aware of deadlock handling isn't specific 2pl.

is correctly understood if t1 transaction has aquired writelock (exclusive) , t2 tries aquire readlock, t2 forced wait?

i know 1 can have writelock, understand 2pl, if transaction modifying (having writelock), transaction cannot read (aquire readlock).

looking forward answers - have great weekend. :-)

/ben


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