copied from http://stackoverflow.com/questions/75675/how-do-i-dump-the-data-of-some-sqlite3-tables
You don't say what you wish to do with the dumped file.
I would use the following to get a CSV file, which I can import into almost everything
 .mode csv 
.header on 
.out file.dmp 
select * from emp;
If you want to reinsert into a different SQLite database then:
 .mode insert 
.out file.sql 
select * from em
