import .db files/tables into sqlite database
For each database file (other.db) that must export tables to main.db:

sqlite3 other.db .dump | sqlite3 main.db


Or if you want to check the generated commands:

sqlite3 other.db .dump &gt; log
sqlite3 main.db &lt; log


Another method: (not so good as it does not import the primary key and column types)

First open the main database:

sqlite3 main.db


Then for each database containing tables to be imported:

ATTACH DATABASE 'other.db' AS other;
CREATE TABLE tablename AS SELECT * FROM other.tablename;
DETACH DATABASE other;