The weak entity set MUST have total participation in the identifying relationship

The owner entity set MUST have total participation in the identifying relationship

Both weak and owner entity sets MUST have total participation in the identifying relationship

Neither weak entity set nor owner entity set MUST have total participation in the identifying relationship

Sorted

Heap

Unclustered tree index

Unclustered hash index

2PL permits only serializable schedules

With 2PL, a transaction always locks the data item being read or written just before every operation and always releases the lock just after the operation

With 2PL, once a lock is released on any data item inside a transaction, no more locks on any data item can be obtained inside that transaction

A deadlock is possible with 2PL

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