Breaking News: Grepper is joining You.com. Read the official announcement!

mysql bidirectional composite primary key

jcho.morpheo answered on February 8, 2021 Popularity 1/10 Helpfulness 8/10

answer mysql bidirectional composite primary key

related mysql bidirectional composite primary key

mysql bidirectional composite primary key

Comment

CREATE TRIGGER uinsert BEFORE INSERT ON tbl_challenger
 FOR EACH ROW SET NEW.u0 = LEAST(NEW.host,NEW.challenger),
  NEW.u1 = GREATEST(NEW.host,NEW.challenger);
#same for update
CREATE UNIQUE INDEX uniqueness ON tbl_challenger(u0,u1);

Popularity 1/10 Helpfulness 8/10 Language sql

Source: stackoverflow.com

Tags: bidirectional composite mysql primary-key sql

Link to this answer
Share Copy Link

Contributed on Feb 08 2021

jcho.morpheo

0 Answers Avg Quality 2/10

Closely Related Answers

mysql bidirectional composite primary key

Comment

create trigger bi_foo before insert on foo
for each row
begin
  if exists(select 1 from foo where bar1 = NEW.bar2 and bar2 = NEW.bar1)
  then
    signal sqlstate '50000' set message_text="Oops";
  end if;
end

Popularity 1/10 Helpfulness 8/10 Language sql

Source: stackoverflow.com

Tags: composite sql mysql primary-key bidirectional

Link to this answer
Share Copy Link

Contributed on Feb 08 2021

jcho.morpheo

0 Answers Avg Quality 2/10

Continue with Google

By continuing, I agree that I have read and agree to Greppers's Terms of Service and Privacy Policy.

mysql bidirectional composite primary key

Contents

More Related Answers

mysql bidirectional composite primary key

Closely Related Answers

mysql bidirectional composite primary key

Grepper

Documentation

Social

Legal

Contact

Oops, You will need to install Grepper and log-in to perform this action.