Hi, I understand that in READ COMMITTED isolation level, SELECT queries reads a snapshot of the database as of the instant the query begins. And also a concurrent transaction(uncommitted) writing to the same table won't block the readers. However, I see that in the heap_update(heapam.c) function there is a brief interval(Lock and unlock the buffer) where a writer may block readers if the writer is updating the same row which readers are reading. Could anyone please help me with the below query?
1) Is my understanding correct? In so, Is it not against the statements "readers does not block writers and writers does not block readers" Best, Ajay
