How to add ASC or DESC to an ORDER BY SQL query

Question

This is an example of a query I've tried:

 const order = req.params.order connection.query('select * from students order by first_name key=?', order, (err)=>{... });

By default without specifying the way, I retrieve the information ordered by first_name asc.

I would like the data ordered by asc or desc according what has been sent through the params.

Answer 1

Im assuming that req.params. order = ASC or DESC. So try this:

connection.query(`select * from students order by fisrt_name ${order}`, order, (err)=>{
...
});

or

const myQuery = `select * from students order by fisrt_name ${order}`;
connection.query(myQuery, order, (err)=>{
...
});

Answer 2

Do this. If order is undefined it will order by ASC by default. If it is defined, it will order by the parameter. I hope this is what you were looking for.

connection.query(
    `select * from students order by first_name ${order ? order : 'ASC'}`
    , order, (err)=>{
...
});