td;lr - "Only one transaction can be granted an SIX lock on a table at a time." Logically it makes sense that T2 and T3 cannot run concurrently. But I understand you are question is then at what case a node will have "SIX" lock right. It is not explained in this tutorial. Hope you can understand it better here (www.radford.edu/~itr-cs/sqltables/c5s20.html)
A very good explanation of intention locks with relevant examples. Hats off!!
Very clear explanation..... Examples are very helpful....
the best video on youtube for multiple granularity locks
thankyou so much sir! its far better explanation ....
great explanation
arleast mention source, he is a proffessor from IIT, featured in one of NPTEL
Quite helpful and explanatory. Thanks.
Why T2 and T3 can not run concurrently ? What about SIX lock?
+Raj Patel T2 and T3 can not be concurrent because at the node f1 the lock compatibility matrix does not hold true i.e between IX and S . 22:35
td;lr - "Only one transaction can be granted an SIX lock on a table at a time."
Logically it makes sense that T2 and T3 cannot run concurrently.
But I understand you are question is then at what case a node will have "SIX" lock right.
It is not explained in this tutorial.
Hope you can understand it better here (www.radford.edu/~itr-cs/sqltables/c5s20.html)
thank u so much sir
Sir, How come IX and X are compatible. how can it write
They aren't compatible. Sir never said that. Also, it is 'N' in the compatibility matrix.
I think it is better to demonstrate how transactions get locks from top to bottom, instead of from bottom to top.