(Solved): check for seralizablity HGURE 20.5 TWO serialization graphs. has many topological sorts, and hence ...
check for seralizablity
HGURE 20.5 TWO serialization graphs. has many topological sorts, and hence there are many conflict-equivalent serial schedules of its transactions. Two of these schedules are T1T2T3T4T5T6T7 and −T1T3T5T2T6T7T4 The sertalization graph in Figure 20.5(b) is obtained from the graph of Figure 20.5(a) by adding the edge T7→T2. It corresponds to a nonserializable schedule because of the cycle T2+T5→T7→T2
In the given Questions There are two edge graphs given i.e. a) and b) we have to Identify serializable schedules out of the given graph.Serializability - The property of ensuring that the execution of concurrent transactions produces the same results as if they were executed serially. In simple words, we can say that if there are five Instructions to execute but some of the instructions are dependent on others for example let's assume Instruction I1, I2, I3, I4, I5. here assume I3 is dependent on I1 (might be using the output of I1 as its input). so in that case we will have to execute I1 before I3 but that doesn't mean we are bound to execute serially we can do it like I1, I3, I2... or we can do it like I4, I2, I1, I5, I3. we can see the instructions are not executing serially but still it won't violate any working of the program so serializable means even if we are not executing the instructions serially because of some internal optimization or for any reason. still, the output will be the same as if it would have been executed serially.