Temporarily disable the foreign key constraint (ALTER TABLE xxx DROP CONSTRAINT fkname), do the import, then use a query or queries to find the problem, fix the data, re-establish the foreign key.
Finding the bad field shouldn't be hard.
Let's say you had table
And when you import some data into the postings table you get a foreign key error.
CREATE TABLE users (
userid INT PRIMARY KEY,
CREATE TABLE postings (
postid INT PRIMARY KEY,
CONSTRAINT posting_user_fk FOREIGN KEY (postedby) REFERENCE users(userid),
So you drop the foreign key
ALTER TABLE postings DROP FOREIGN KEY posting_user_fk, do the import, and then do something like:
Presto. That finds all the records with problems, and then you can go in and fix just those records (or delete them). When they are all fixed, re-create the FOREIGN KEY.
FROM postings AS P LEFT JOIN users AS U ON P.postedby = U.userid
WHERE U.userid IS NULL