Fast data copy with “Create Table Select From” in PL/SQL

 tried creating temp table normally and copied the data using normal INSERT INTO SELECT query:

INSERT INTO TA SELECT * FROM A

This approach took a lot of time to execute.

Then I tried creating same temp table with different syntax. I tried CREATE TABLE SELECT FROM syntax of PL SQL for creating as well as copying the data into temp table:

CREATE TABLE TA AS SELECT * FROM A

The second approach was amazingly fast. The above sql can be generalized to create table as follow:

CREATE TABLE new_table_name [ ( column [, ...] ) ] AS SELECT [ ( column [, ...] ) ] FROM existing table_name