Now I create another database where this CPK is converted into surrogate key for table ‘A1′. Now, I want to reference the data in my table ‘B1′ with this surrogate key. (note A1 and B1 are in different database.)

Can anyone help me how to do it?

Please let me know if you need more information.

primary key(fk_author_id , blog_id),

would be

primary key(fk_blogger_id , blog_id),

create table blog(
fk_blogger_id int(10),
blog_id int(10) auto_increment,
….other columns,
primary key(fk_author_id , blog_id),
unique key (blog_id),
foreign key (fk_blogger_id) references blogger(blogger_id)
) ENGINE=InnoDB;

“blogger” is a separate table of bloggers.

Now, say i have say 1-2 blog inserts every second posted by a random bloggers.
would it be a efficient table design?
I would prefer this design as it groups blogs per blogger. Direct access of a blog will use the unique index of blog_id and that would result in two index lookups. But as i would show other blogs of same blogger on the page, The grouping would speed up the overall efficiency.

Am I thinking right? are there any benchmarks around similar solution

great stuff though!

As Xaprb said, your second insert is slow because you are inserting in a random order. Before loading, sort your data in primary key order and the two inserts should run in similar time.