1. What is the difference between a transaction having exclusive access or shared access to an item in a database and why is the distinction important? 2. The problems discussed in Section 9.4...

1.
What is the difference between a transaction having exclusive access or shared access to an item in a database and why is the distinction important?

2.
The problems discussed in Section 9.4 involving concurrent transactions are not limited to database environments. What similar problems would arise when accessing a document

with word processors? (If you have a PC with a word processor, try to access the same document with two activations of the word processor and see what happens.)