"update by query" not working as expected with straight calls

Question

I've an script that calls Elasticsearch with some update_by_query.

Here I update the item with id=299966 and change the trash flag, trash=0:

_update_by_query
{
  "query": {
    "query": {
      "bool": {
        "must": [
          {
            "terms": {
              "_id": [
                299966
              ]
            }
          }
        ],
        "should": [

        ]
      }
    }
  },
  "script": {
    "inline": "ctx._source.trash=0"
  }
}

Then I the item with id=299966 (same item as above) to trash=1:

_update_by_query
{
  "query": {
    "query": {
      "bool": {
        "must": [
          {
            "terms": {
              "_id": [
                299966
              ]
            }
          }
        ],
        "should": [

        ]
      }
    }
  },
  "script": {
    "inline": "ctx._source.trash=1"
  }
}

The thing is that after doing this two operations, if I search for the item with id=299966, I get trash=0, when it's supposed to be trash=1 as it's the last one executed. I always mantain the order and my own log shows that the one with trash=0 is first executed, and then the one with trash=1.

Is there any stuff inside the update_by_query logic that avoids to make two calls? Do I have to wait some seconds or something to make the second update_by_query?

PS: Nervemind those double query on the codes. It's working ok.

Thanks in advance.

Answer 1

The solution I found is to use _flush after every _update or every _update_by_query.

myindex/_update_by_query
{
  "query": {
    "query": {
      "bool": {
        "must": [
          {
            "terms": {
              "_id": [
                299966
              ]
            }
          }
        ],
        "should": [

        ]
      }
    }
  },
  "script": {
    "inline": "ctx._source.trash=0"
  }
}

myindex/_flush

myindex/_update_by_query
{
  "query": {
    "query": {
      "bool": {
        "must": [
          {
            "terms": {
              "_id": [
                299966
              ]
            }
          }
        ],
        "should": [

        ]
      }
    }
  },
  "script": {
    "inline": "ctx._source.trash=1"
  }
}