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lib/dialects/abstract/query.js

@@ -347,6 +347,11 @@ module.exports = (function() {
    * Previous set won't necessarily be parent set (one parent could have two children, one child would then be previous set for the other)
    */
 
+  /*
+   * Author (MH) comment: This code is an unreadable mess, but its performant.
+   * groupJoinData is a performance critical function so we prioritize perf over readability.
+   */
+
   var groupJoinData = function(rows, includeOptions, options) {
     if (!rows.length) {
       return [];