Using the LOAD DATA INFILE
SQL statement you can import the CSV file, but you can't update data. However, there is a trick you can use.
Load onto this table from the CSC
LOAD DATA LOCAL INFILE '/file.csv'
INTO TABLE temp_table
FIELDS TERMINATED BY ','
LINES TERMINATED BY '\n'
(field1, field2, field3);
UPDATE the real table joining the table
UPDATE maintable
INNER JOIN temp_table A USING (field1)
SET maintable.field1 = temp_table.field1