Answer Posted / pr@$@d

1 TRUNCATE is a DDL command whereas DELETE is a DML command.
2 TRUNCATE is much faster than DELETE.
Reason:
a) When you type DELETE. All the data get copied into
the Rollback Table space first. Then delete operation get
performed. That’s why when you type ROLLBACK after deleting
a table, you can get back the data (The system gets it for
you from the Rollback Table space).All this process takes
time. But when you type TRUNCATE, it removes data directly
without copying it into the Rollback Tablespace.Thatswhy
TRUNCATE is faster. Once you truncate you can’t get back
the data.
b) TRUNCATE command resets the High Water Mark for the
table but DELETE does not. So after TRUNCATE the
operations on table are much faster.
3 You can’t rollback in TRUNCATE but in DELETE you can
rollback. TRUNCATE removes the record permanently.
4 In case of TRUNCATE, Trigger doesn't get fired.But in DML
commands like DELETE .Trigger get fired.
5 You can’t use conditions (WHERE clause) in TRUNCATE.But
in DELETE you can write conditions using WHERE clause

Regards,
-Pr@$@d Reddi.
prasadreddi_mca@yahoo.com

How to define an anonymous block?

1160

---

A table t is there.If you perform insert ,update and delete then the trigger will fire.What is the minimum no of trigger required for a table.

5563

---

Explain user account with reference to oracle.

993

---

What is a table in oracle?

982

---

What is oracle host variable?

1068

---

What is connection pooling in oracle?

974

---

What is the use of file param in imp command?

1165

---

What is a trigger and what are its types in oracle?

1075

---

How can you use check constraints for self referential integrity?

971

---

How to drop a stored function?

1139

---

How to create a table in a specific tablespace?

977

---

Explain the difference between sap and oracle?

1033

---

What is merge statement used for?

1025

---

What is a select query statement in oracle?

970

---

Where are the settings stored for each instance in oracle?

1106

---