Multiple MySQL queries returning undefined when outputting value

Question

I am running two database queries to retrieve data that I will outputting in a message embed. The queries are returning the proper rows when I just dump the entire result into the console. However, whenever I try to output the actual value for one of the rows, it displays as undefined in the message embed.

From what I've found based on examples, rows[0].somevalue should be outputting the correct results.

let mentionedUser = message.mentions.members.first();
let captainUser = client.users.find(user => user.id == `${mentionedUser.id}`);

con.query(`SELECT * FROM captains WHERE id = '${mentionedUser.id}';SELECT * FROM results WHERE captain = '${captainUser.username}'`, [2, 1], (err, rows) => {
    if(err) throw err;

    console.log(rows);

    const infoEmbed = new Discord.RichEmbed()
        .setColor("#1b56af")
        .setAuthor('Captain Information', client.user.displayAvatarURL)
        .setThumbnail('https://i.imgur.com/t3WuKqf.jpg')
        .addField('Captain Name', `${mentionedUser}`, true)
        .addField('Cap Space', `${rows[0].credits}`, true) // Returns undefined
    message.channel.send(infoEmbed);

    });

This is the console result

[ [ RowDataPacket {
      id: '91580646270439424',
      team_name: 'Resistance',
      credits: 85,
      roster_size: 2 } ],
  [ RowDataPacket { id: 'Sniper0270', captain: 'BTW8892', credits: 10 },
    RowDataPacket { id: 'Annex Chrispy', captain: 'BTW8892', credits: 5 } ] ]

In the code posted above, the expected output of rows[0].credits should output 85. No error codes are present, it just displayed as "undefined" in the message embed.

Deadron · Accepted Answer · 2019-06-08 20:37:14Z

1

You are executing two queries inside a single query call. It looks like the mysql library returns an array of arrays in this scenario where the first value is the result of the first query and the second is the result of the second query. This is non standard. Normally you would either execute each query in its own query call or you would use a union to join the two queries into a single resultset.

answered Jun 8, 2019 at 20:37

Deadron

5,2891 gold badge18 silver badges28 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Ali kazmi · Accepted Answer · 2019-06-08 21:39:18Z

0

this is not the practical way to send query request , as query is a single statement excluding the bulk update , you cannot execute two different query using a single con.query , it is not a proper way. execute them separately

answered Jun 8, 2019 at 21:39

Ali kazmi

11 bronze badge

Collectives™ on Stack Overflow

Multiple MySQL queries returning undefined when outputting value

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related