How to store socket value in mySQL database from Node.js?

Question

JavaScript

Node.js Almost none. )))
I am writing a chat server. Clients are all console. Communicate individually, that is, there is no "broadcasting at all."
Question 1.
Is it possible in NODE js to somehow arrange a dynamically growing array of the type:
[id1] [socket_in] [socket_out]
[id2] [socket_in] [socket_out]
....
[idn] [socket_in] [socket_out]

Question 2.
If I already have a mySQL database, how can I store the socket in it? What type of cell can do this?
I don't know myself (((
Thanks for the help.
My initial state, I don't know how to save the client socket.

var net = require('net');
var mysql = require('mysql');
//var clients = [];

net.createServer(function(socket){
  var connection = mysql.createConnection({
    host : '127.0.0.1',
    port : 3306,
    database: 'node',
    user : 'root',
    password : ''
  });
  connection.connect(function(err){
        if(err != null) {
            console.log('Error connecting to mysql');
        }
    else {
            console.log('[+]client connected to mysql');			
    }
    });
///////////////////////////////////////////////////////////////////////////////	
    socket.on('data', function(request) {
    var indata = request.toString("binary");
    //console.log(indata+'\r');
    var msg = indata.trim();
    console.log('after trimming message is: ' + msg);
    if( msg.substr(0,3) === '/w '){
      // Если клиент задал "/w" 		
      var ind = msg.indexOf(' ');
      if(ind !== -1){
      } 
    }
    else{
      console.log(msg);
      // Если клиент не задал "/w" нужно сохранить сокет в базе ........ ?
    }
  });
  //connection.end(function(err){
    //        console.log('[+]client disconnected from mysql');			
    //});	
///////////////////////////////////////////////////////////////////////////////
  socket.on('disconnect', function(socket) {
    console.log('[+]client disconnected'); 	
  });
    socket.on('end', function(socket) {
    console.log('[+]client ending'); 
  });
      socket.on('close', function(socket) {
    console.log('[+]client closing'); 
  });   
    socket.on('error', function(socket) {
    console.log('[+]error from client'); 
  }); 
}).listen('8888');
console.log('for connect use 127.0.0.1:8888'+'\r\n');

Answer 1

1) All arrays in JS are dynamic. Use the Array#push method to add a new element to the end.
2) Assign a unique id to each socket and store it in the database (although it is not clear why this is).

Answer 2

Thank you.
... well, what if I have all console chat clients (just putty), but I won't be able to send and process messages? And how would the declaration of an array of size (4 to infinity) look like?
And how to remove an element from it?