Answer Posted / raji_4u

in share mode :
this mode is for read only on entire table.
we can not make changes to table.
any user can have a lock in share mode at same time.

in share update mode :
this mode is used to lock the selected rows for update.
this mode acquires lock on selected rows only,not entire table.
other user can have lock on other rows on the same table but
not on the rows you have locked.

in exclusive mode :
this acquires lock on entire table.
another user can not have any lock on that table.

What is union and union all keyword in sql?

566

---

What is a database event trigger?

594

---

what are date and time functions in mysql? : Sql dba

533

---

What does stand for in sql?

523

---

What are sql queries used for?

535

---

---

What is the purpose of the sql select top clause?

557

---

Can you select everything, but 1 or 2 fields, without writer's cramp?

497

---

What is primary key secondary key alternate key candidate key?

544

---

What is natural join in sql?

536

---

What is right join in sql?

552

---

What is consistency?

714

---

How to assign sql query results to pl sql variables?

510

---

How do you optimize a stored procedure query?

566

---

What is triggering circuit?

597

---

Mention what does the hierarchical profiler does?

561

---