Question

I’d like to use the ‘insert into’ mysql command to move table1 contents to table2, but table2 may have the ‘same’ primary keys. I want to replace the table2’s record (that have the same primary key) with table1’s record when the insert statement is executed. Can I use ‘or replace’ to make this happen?

Answer 1

Use an INSERT … SELECT with an ON DUPLICATE KEY UPDATE clause:

INSERT INTO table2 
  SELECT * FROM table1 ON DUPLICATE KEY UPDATE table2.field1 = table1.field1

note using * for brevity, but in the update clause you must specify the fields individually, and should do so in the insert and select clauses as well.