I did this function to join between 2 tables but I think that is not the right way
function insertarDatosToArchivos(){
objBD.query('SELECT ID_U from usuario', function(err, rows, fields) {
for (var i = 0; i < rows.length; i++) {
objBD.query('SELECT ID_L from LETRA where rows[i].ID_U=LETRA.ID_U', function(err, rows, fields) {
});
};
});
};
I think it's simpler if you do the query in a single call to mysql . Something like this:
function insertarDatosToArchivos(){
objBD.query('SELECT u.ID_U, l.ID_L from usuario u INNER JOIN LETRA l ON u.ID_U = l.ID_U', function(err, rows, fields) {
//Tu código de lógica acá
}});
};
In this way you optimize the number of calls to the database and in turn the execution time of your function.