Question

I’m trying to import a CSV file into a MySQL 5.1 DB using phpMyAdmin. The file includes several date columns which may contain NULL values. According to the manual, NULL should be written as \N. However, after an otherwise successful import, \N appears as 0000-00-00 in the date columns (as opposed to NULL). How do I get NULLs imported?

Options set:

• line separator ,
• fields enclosed by ",
• fields escaped by \,
• lines terminated by auto.

Answer 1

phpMyAdmin distinguishes two CSV import formats: CSV and CSV with LOAD DATA. The latter option actually accepts \N as described in the manual.

If columns are enclosed by a character (as it is the case), NULLs may also be imported using the former method (no LOAD DATA) by setting a value to a non-enclosed NULL in the CSV file. This is in accordance with the manual‘s following statement:

If FIELDS ENCLOSED BY is not empty, a field containing the literal
word NULL as its value is read as a NULL value. This differs from the
word NULL enclosed within FIELDS ENCLOSED BY characters, which is read
as the string ‘NULL’.