Exporting to CSV. Error Code: 2013. Lost connection to MySQL server during query

[Fred G]

Hi--

I'm trying to do the following:
SELECT db.emp.emp_fname, db.emp.emp_fname, db.sale.sale_date,
db.sale.sale_no, db.sale.sale_total_amt
into outfile 'test123.csv'
FIELDS terminated by ','
FROM db.emp
LEFT OUTER JOIN db.sale
ON db.sale.emp_id = db.emp.emp_id;

The query without exporting the file works fine, in about 12 sec/77 sec.  I
read online how to export MySQL queries into csv's, and I'm not sure what I
am doing wrong.  I keep getting the error:
Error Code: 2013.  Lost connection to MySQL server during query, where the
duration/fetch values are 600.547 sec (~10 minutes).

I'm wondering:
a) What is going on?
b) How do I fix it?

Thanks so much!!