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  1. Couchbase Server
  2. MB-20980

Wrongly pushed the limit from Outer subquery to Inner subquery

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Details

    • Bug
    • Resolution: Fixed
    • Major
    • 4.5.1, 5.0.0
    • 4.5.0, 4.5.1, 5.0.0
    • query
    • None
    • Untriaged
    • Yes
    • Query-Sprint-09-19-2016

    Description

      This only happens when outer has limit and inner doesn't have limit.
      All other cases it works.

      create index ix30 on default(f1);
      EXPLAIN select f1 FROM (select f1 from default where f1 is not missing ) q   limit 15;
       EXPLAIN select * FROM (select * from default where f1 is not missing ) q   limit 15;
      {
          "requestID": "34e915dd-1938-4ce1-9eca-e8d6bbba952c",
          "signature": "json",
          "results": [
              {
                  "plan": {
                      "#operator": "Sequence",
                      "~children": [
                          {
                              "#operator": "Sequence",
                              "~children": [
                                  {
                                      "#operator": "Sequence",
                                      "~children": [
                                          {
                                              "#operator": "IndexScan",
                                              "index": "ix30",
                                              "index_id": "7c6298d7e5a93df",
                                              "keyspace": "default",
                                              "limit": "15",
                                              "namespace": "default",
                                              "spans": [
                                                  {
                                                      "Range": {
                                                          "Inclusion": 1,
                                                          "Low": [
                                                              "null"
                                                          ]
                                                      }
                                                  }
                                              ],
                                              "using": "gsi"
                                          },
                                          {
                                              "#operator": "Fetch",
                                              "keyspace": "default",
                                              "namespace": "default"
                                          },
                                          {
                                              "#operator": "Parallel",
                                              "~child": {
                                                  "#operator": "Sequence",
                                                  "~children": [
                                                      {
                                                          "#operator": "Filter",
                                                          "condition": "((`default`.`f1`) is not missing)"
                                                      },
                                                      {
                                                          "#operator": "InitialProject",
                                                          "result_terms": [
                                                              {
                                                                  "expr": "self",
                                                                  "star": true
                                                              }
                                                          ]
                                                      },
                                                      {
                                                          "#operator": "FinalProject"
                                                      }
                                                  ]
                                              }
                                          }
                                      ]
                                  },
                                  {
                                      "#operator": "Alias",
                                      "as": "q"
                                  },
                                  {
                                      "#operator": "Parallel",
                                      "~child": {
                                          "#operator": "Sequence",
                                          "~children": [
                                              {
                                                  "#operator": "InitialProject",
                                                  "result_terms": [
                                                      {
                                                          "expr": "self",
                                                          "star": true
                                                      }
                                                  ]
                                              },
                                              {
                                                  "#operator": "FinalProject"
                                              }
                                          ]
                                      }
                                  }
                              ]
                          },
                          {
                              "#operator": "Limit",
                              "expr": "15"
                          }
                      ]
                  },
                  "text": "select * FROM (select * from default where f1 is not missing ) q   limit 15;"
              }
          ],
          "status": "success",
          "metrics": {
              "elapsedTime": "2.579336ms",
              "executionTime": "2.560735ms",
              "resultCount": 1,
              "resultSize": 4634
          }
      }
      

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              Prerna.Manaktala Prerna Manaktala (Inactive)
              Sitaram.Vemulapalli Sitaram Vemulapalli
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              Dates

                Created:
                Updated:
                Resolved:

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