Optimize if output format is SQLite

If we run the following command:

rows query 'SELECT * FROM table1 WHERE field1="value1"' filename.sqlite --output=out.sqlite

the CLI will:

• Connect to a SQLite database named filename.sqlite since there's only one source and it's format is SQLite
• Import the SQLite result into a rows.Table running the query
• Export the result rows.Table into a new SQLite database named out.sqlite

We can optimize this use case replacing the steps with the following:

• Connect to a SQLite database named filename.sqlite since there's only one source and its format is SQLite
• Attach the output database with SQLite's ATTACH SQL command
• Change the query to have INSERT INTO (to add result to the new database)
• Run the query

More details on ATTACH in StackOverflow this thread.