Nested Whiles

[JoshuaW]

Hi all,

I would like to share this, whilst putting this together using nested whiles.

• 1st Table are list of categories

• 2nd Tables are customer's assigned categories

Incorrect way

Code: Select all

var cats = table.CATEGORIES.rows;
var owns = tables.OWN_CATEGORIES.rows;
while(cats.next()){
  while(owns.next()){
     if(tables.CATEGORIES.CAT_ID.value == tables.OWN_CATEGORIES.CAT_ID.value){
       log('loop2: ' + tables.OWN_CATEGORIES.CAT_ID.value);
       break;
     }
  }
}

Suggested method using nested whiles

Code: Select all

var cats = table.CATEGORIES.rows;
while(cats.next()){
  var owns = tables.OWN_CATEGORIES.rows;
  while(owns.next()){
     if(tables.CATEGORIES.CAT_ID.value == tables.OWN_CATEGORIES.CAT_ID.value){
       log('loop2: ' + tables.OWN_CATEGORIES.CAT_ID.value);
       break;
     }
  }
}

Although if any CATEGORIES have duplicated rows for different purposes, then a while break is not recommend.

[Steve]

Hi Joshua,

I would tweak so that you break out of the outer (cats) loop too.

Code: Select all

var cats = table.CATEGORIES.rows;
var match = false;
while(cats.next()){
  var owns = tables.OWN_CATEGORIES.rows;
  while(owns.next()){
     if(tables.CATEGORIES.CAT_ID.value == tables.OWN_CATEGORIES.CAT_ID.value){
       log('loop2: ' + tables.OWN_CATEGORIES.CAT_ID.value);
       match = true;
       break;
     }
  }
  if(match)
    break;
}

Otherwise you will iterate through all the tables rows again on the next iteration of cats.

Thanks

Steve