I have limit of 12 items, but dynamodb query always returns 10 only

Question

I'm using dynamodb npm to query dynamodb

When I query as below, though I set limit as 12 items, It always returns 10 items

TableDB
  .query(lang)
  .filter('users').in(['case1','case2'])
  .attributes(['offerId', 'lang'])
  .ascending()
  .usingIndex('lang-date-index')
  .limit(12)
  .exec((err, data) => {
    console.log(data)
  }

I don't want to query again using lastEvaluateKey just for next 2 items.

Am I missing something?

What about if you try using limit less than 10? It will return correct amount? If so. Maybe you have in server settings limit to return results of 10 max? If limit < 10 will not work than it's problem with limit method in module itself. Hope this will helps. — Mykola Borysyuk, Dec 12 '17 at 08:18
After debugging come to know if I remove `.filter` it gives 12 results, If I apply `.filter` it gives 10 results with `lastEvaluateKey`(means it has more results). @Mykola It works if I have less than 5 results — Jagdish Idhate, Dec 12 '17 at 08:21
Maybe this will provide some info https://stackoverflow.com/questions/40138551/how-can-i-do-dynamodb-limit-after-filtering — Mykola Borysyuk, Dec 12 '17 at 08:25
Thanks @MykolaBorysyuk for link, I guess I need to reiterate for next page. — Jagdish Idhate, Dec 12 '17 at 08:32

score 13 · Accepted Answer · answered Dec 12 '17 at 09:21

Dynamo applies limit first and only then filters. See Scan limit. This means, if your table has 3 items in the order below :

Dog1
Cat1
Dog2

You filter by dogs and your read limit is 2 then you get following result set:

Dog1

The dynamo response will also provide LastEvaluatedKay which is the last read primary key on your table. Set this LastEvaluatedKay as ExclusiveStartKey in your next results. Here's a similar example of pagination loop for dynamo (in java).

score 0 · Answer 2 · answered Dec 12 '17 at 09:17

0

Have you tried

.loadAll()

The docs aren't too clear on what this does, but it sounds promising.

answered Dec 12 '17 at 09:17

F_SO_K

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I have limit of 12 items, but dynamodb query always returns 10 only

2 Answers2