如何比较不同表中的2列，并使用MYSQL在新表中插入不匹配的记录？

I need to compare 2 fields in two tables to find unmatched records and insert those records in a new table

Try this

Create a table(new_table) with required fields

INSERT INTO new_table 
SELECT table1.field1, table2.field2 FROM table1, table2
WHERE (
table1.field_name != table2.field_name
);