topic QueryTask not returning results when it should! in ArcGIS JavaScript Maps SDK Questions

QueryTask not returning results when it should!

JayGregory — Fri, 10 Dec 2021 23:30:55 GMT

So I am trying to do something very simple - return the points for the USGS Steam Flow Station layer (http://rmgsc.cr.usgs.gov/ArcGIS/rest/services/nhss_usdata/MapServer/0) that fall within the District of Columbia. There should be 3.

First I construct a QueryTask to get the District of Columbia layer

      var queryTask = new esri.tasks.QueryTask(districtURL);
  var query = new esri.tasks.Query();
               query.returnGeometry = true;
               query.outFields = ["*"];
        query.where = "CITY_NAME = 'Washington'"
               query.outSpatialReference = map.spatialReference;
        queryTask.execute(query, queryResults, errorCall);

I've verified that this works - one feature is returned. However, when I try to query the points in Steam Flow Station layer against this result, I get an error since null results are returned!

function queryResults(featureSet){
      console.log(featureSet.spatialReference);
     console.log(map.spatialReference);
     var queryTaskWithin = new esri.tasks.QueryTask("http://rmgsc.cr.usgs.gov/ArcGIS/rest/services/nhss_usdata/MapServer/0");
     var query = new esri.tasks.Query();
            query.returnGeometry = true;
     query.outFields = ["*"];
     query.outSpatialReference = map.spatialReference;
     query.spatialRelationship = esri.tasks.Query.SPATIAL_REL_WITHIN;
     query.geometry = featureSet.features[0].geometry;
     queryTaskWithin.execute(query)
     dojo.connect(queryTaskWithin, "onComplete", function(fset) {
 console.log(fset.features.length);
 }, function(error){console.log("error" + error)});
}

At one point I was getting 0 results and no error, but now I'm just getting an error. I thought this should be a simple task - any assistance would be of great help.

Also, the spatial references of the district layer and the Steam Flow Station layer are seemingly different. One is 102100 and the other is 3857. But I think those are both web mercator so it shouldn't matter too much, right?

Thanks!

Jay

Re: QueryTask not returning results when it should!

HemingZhu — Fri, 10 Dec 2021 23:30:58 GMT

So I am trying to do something very simple - return the points for the USGS Steam Flow Station layer (http://rmgsc.cr.usgs.gov/ArcGIS/rest/services/nhss_usdata/MapServer/0) that fall within the District of Columbia. There should be 3.

First I construct a QueryTask to get the District of Columbia layer
      var queryTask = new esri.tasks.QueryTask(districtURL);
  var query = new esri.tasks.Query();
               query.returnGeometry = true;
               query.outFields = ["*"];
        query.where = "CITY_NAME = 'Washington'"
               query.outSpatialReference = map.spatialReference;
        queryTask.execute(query, queryResults, errorCall);
I've verified that this works - one feature is returned. However, when I try to query the points in Steam Flow Station layer against this result, I get an error since null results are returned!
function queryResults(featureSet){
      console.log(featureSet.spatialReference);
     console.log(map.spatialReference);
     var queryTaskWithin = new esri.tasks.QueryTask("http://rmgsc.cr.usgs.gov/ArcGIS/rest/services/nhss_usdata/MapServer/0");
     var query = new esri.tasks.Query();
            query.returnGeometry = true;
     query.outFields = ["*"];
     query.outSpatialReference = map.spatialReference;
     query.spatialRelationship = esri.tasks.Query.SPATIAL_REL_WITHIN;
     query.geometry = featureSet.features[0].geometry;
     queryTaskWithin.execute(query)
     dojo.connect(queryTaskWithin, "onComplete", function(fset) {
 console.log(fset.features.length);
 }, function(error){console.log("error" + error)});
}
At one point I was getting 0 results and no error, but now I'm just getting an error. I thought this should be a simple task - any assistance would be of great help.

Also, the spatial references of the district layer and the Steam Flow Station layer are seemingly different. One is 102100 and the other is 3857. But I think those are both web mercator so it shouldn't matter too much, right?

Thanks!

Jay

I think the issue is your query.spatialRelationship. Comment it out, and see what happen.

Re: QueryTask not returning results when it should!

JoshuaTanner — Tue, 17 Apr 2012 17:03:42 GMT

Try unprojecting the coordinates:

Code:

query.geometry = esri.geometry.webMercatorToGeographic(featureSet.features[0].geometry);

-Josh

Re: QueryTask not returning results when it should!

JayGregory — Wed, 18 Apr 2012 00:10:06 GMT

Josh - thanks for the suggestion. I tried that, and it still doesn't work. When I set the extent to the returned geometry of the first query (returning the DC borders), it zooms to the coast of Africa like there was no project, although the spatial Reference is 3857, and the original DC layer draws in the correct location on a base map. Any suggestions?

Thanks, Jay

Re: QueryTask not returning results when it should!

Anonymous User — Tue, 24 Apr 2012 18:28:56 GMT

I am having the same issue with the querytask. I am getting a null returned as well. My code is similar to Jay's although I am using a different Map service and layer of course. Can someone help with this issue???

Thanks,

Re: QueryTask not returning results when it should!

derekswingley1 — Tue, 24 Apr 2012 19:29:07 GMT

I am having the same issue with the querytask. I am getting a null returned as well. My code is similar to Jay's although I am using a different Map service and layer of course. Can someone help with this issue???

Thanks,

Please start a new thread and post some code that shows the issue.

Re: QueryTask not returning results when it should!

Anonymous User — Tue, 24 Apr 2012 20:06:48 GMT

I have posted the answer that I found, which worked for me in a seperate post: http://forums.arcgis.com/threads/56118-QueryTask-not-showing-results-when-it-should

Re: QueryTask not returning results when it should!

derekswingley1 — Tue, 24 Apr 2012 20:25:49 GMT

Thanks. Would have been useful to know you're using Flex, not JavaScript ;).