fix: add orderBy as an option to model discoveries

Signed-off-by: Muhammad Aaqil <aaqilcs102@gmail.com>

Author: aaqilniz

lib/discovery.js

@@ -154,7 +154,7 @@ function mixinDiscovery(MySQL, mysql) {
    * @param table
    * @returns {String} The sql statement
    */
-  MySQL.prototype.buildQueryColumns = function(schema, table) {
+  MySQL.prototype.buildQueryColumns = function(schema, table, options) {
     let sql = null;
     if (schema) {
       sql = paginateSQL('SELECT table_schema AS "owner",' +
@@ -186,7 +186,9 @@ function mixinDiscovery(MySQL, mysql) {
         (table ? ' WHERE table_name=' + mysql.escape(table) : ''),
       'table_name, ordinal_position', {});
     }
-    sql += ' ORDER BY ordinal_position';
+    if (options.orderBy) {
+      sql += ' ORDER BY ' + options.orderBy;
+    }
     return sql;
   };