select - MySQL - Combine two tables into third without duplicates -

i having hard time wrapping mind around concept here. have 3 tables identical structure. need table 1 combined table 2 , insert into table 3. issue:

table 1 , table 2 have duplicate content, exception being id. not using id other ai however, not concern.

an example of looking accomplish is:

                        original table 1  _________________________________________________________ |    id   |      col 2     |     col 3    |      col 4    | |---------------------------------------------------------| |   1     |     stuff_1    |     stuff_2  |     stuff_3   | |---------------------------------------------------------| |   2     |     stuff_x    |     stuff_y  |     stuff_z   | |_________________________________________________________| 

combine with

                        original table 2  _________________________________________________________ |    id   |      col 2     |     col 3    |      col 4    | |---------------------------------------------------------| |   3     |     stuff_1    |     stuff_2  |     stuff_3   | |---------------------------------------------------------| |   4     |     stuff_a    |     stuff_b  |     stuff_c   | |_________________________________________________________| 

to make

combined table 3 (notice id's not counted in duplicate check)  _________________________________________________________ |    id   |      col 2     |     col 3    |      col 4    | |---------------------------------------------------------| |   ?     |     stuff_1    |     stuff_2  |     stuff_3   | |---------------------------------------------------------| |   ?     |     stuff_x    |     stuff_y  |     stuff_z   | |---------------------------------------------------------| |   ?     |     stuff_a    |     stuff_b  |     stuff_c   | |_________________________________________________________| 

i have tried insert table 3 select * table 2; , doing insert ignore table 1. i've tried replace into well, because omitting id, don't work because column count off. have ideas how combine these 2 third table while dealing id issue? reiterate not matter id's not ever used.

you can use group by flatten out duplicates while leaving id value.

this give unique col1, col2 , col3 values, , set id minimum id value rows merged duplicated:

insert table3 (id, col1, col2, col3) select min(id), col1, col2, col3 (   select id, col1, col2, col3 table1   union select id, col1, col2, col3 table2 ) table1and2 group col1, col2, col3 

with posted data, result should this:

id    col1     col2     col3 --    -------  -------  -------  1    stuff_1  stuff_2  stuff_3  2    stuff_a  stuff_b  stuff_c  4    stuff_x  stuff_y  stuff_z