Help, I have 3 identical tables with similar data, now I want to create a 4th table with only unique data from all the 3 tables.

Answer 1

but why , it will not work

Answer 2

use foreign key for connecting tables ... and put primary key on those columns on which u r applying foreign k. to connect tables

Answer 3

use Distinct keyword

Answer 4

SELECT DISTINCT (COL_NAME) FROM TABLE(S) NAME

Answer 5

@sahu I need to do it with all the three combined together.

Answer 6

@sahu I don't want distinct from each table itself but unique data from each table.

Answer 7

@Gaurav that will not work.

Answer 8

@Gaurav the three tables were originally installed on 3 separate machines, then they were imported into a single database, therefore they have no common key.