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How do I sort Firebase Keys in ascending order?

I have a list of products in my Firebase database. My SKU looks like this c08p10

. But the problem is that after the tenth product, a hundred products are displayed.

Please refer to the screenshot for the mixed order.

enter image description here

I understand that the products are ordered alphabetically. But how can I display products in the following order

c08p10
c08p11
c08p12

Note

I can fill in the data in the List view or Recyclers view. But the products are located in the order of the Firebase DB. If I try to change the order. It gives below structure.

c08p118
c08p117
c08p116
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1 answer


Firebase keys are strings. And when you order string data, it is lexicographically ordered.

So, for numbers, this is the normal order:

  • 1
  • nine
  • ten
  • eleven

But for strings, this is the normal order:



  • "1"
  • "eleven"
  • "nineteen"
  • "nine"

There is no operator in Firebase (or most other databases) to change this behavior. Instead, you will need to modify the data to get the behavior you want. So: keep the values ​​that are in the order you want them when sorting lexicographically. For numbers, you can do this by padding them with zeros:

  • "001"
  • "009"
  • "011"
  • "019"

Or in your case c09p010

, etc.

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