mysql - Add user if not exists in another table -


i need add usernames users_waiting table if not added users table before.

var usernamesarray = ['test', 'test2']; connection.query('replace users_waiting (username) values ?', [usernamesarray]);

i'm using node.js mysql client , have no idea how that.

you have many options of doing it. 1 of not exists() :

insert <table2> (...) select .... <source> t not exists(select 1 <table1> s                  t.id = s.id);

i don't think it's need. can figure out rest this.


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