Question

我正在尝试通过API将Google Fusion表格用作Google地图中的图层。只需使用FusionTableLayer（）将图层添加到Google地图就行了。我可以看到地图和所有。＆＃34;有趣＆＃34;当我尝试将过滤器（即＆＃34; where子句＆＃34;）应用于选择查询或样式部分时开始。过滤器不起作用！它不会抛出任何错误。地图继续工作。但是结果集没有被过滤掉 - 好像where子句甚至没有。对于＆＃39;其中＆＃39;的相同症状。用于样式部分的子句。它完全被忽略了。我有三种不同的样式，我想根据过滤条件应用它。所有这些都被忽略了。奇怪的是，样式块中列出的最后一个样式部分将应用于融合表层中的所有要素。我通过切换部分来验证它。我尝试用＆＃34; col10＆＃34;等引用替换实际的字段名称，但这没有任何区别。

我错过了什么？我怎样才能启用＆＃34;在我的FusionTableLayer中使用WHERE子句，以便它们既可以在Select查询中应用，也可以在Styles部分中应用？

注意：在下面的代码段中，为此帖子插入了（//）注释。我正在开发的实际页面/代码中不存在这些注释。

  layer = new google.maps.FusionTablesLayer({
  map: map,
  heatmap: { enabled: false },
  query: {
     select: "col11",
     from: "1D6d93-0iT2zUCw8IvkbpDPYDx2-jA0ZAWXi07mQD",
     //the following filter in select query does not work! 
     //I replaced col10 with actual field name (shift_id) but still EVERYTHING from the table is returned
     where: "col10 <= 3" 
  },
        styles: [{
          //this where clause has no effect. I've tried replacing shift_id with col10.
          where: "((shift_id != 1) AND (shift_id != 2))",
          polylineOptions: {
            strokeColor: "#FFFFFF",
            strokeWeight: "3"  }
        }, {
          //this where clause has no effect. I've tried replacing shift_id with col10.
          where: "shift_id == 1",
          polylineOptions: {
            strokeColor: "#FF0000",
            strokeWeight: "3"  }
        }, {
          //this where clause has no effect. I've tried replacing shift_id with col10.
          //whichever of these three blocks is listed last is the one that gets applied to the layer.
          where: "shift_id == 2",
          polylineOptions: {
            strokeColor: "#ffbf00",
            strokeWeight: "3"  }
        }] 
});

Answer 1

两个建议：

确保您在选择查询中过滤的列被格式化为数字，而不是文本，因为您正在检查<=;以及
列名称区分大小写 - 您在Fusion表中使用了大写SHIFT_ID。

Answer 2

“==”不起作用，请使用“=”
不包括主查询中的位置

layer = new google.maps.FusionTablesLayer({
    map: map,
    heatmap: {
        enabled: false
    },
    query: {
        select: "geometry",
        from: "1D6d93-0iT2zUCw8IvkbpDPYDx2-jA0ZAWXi07mQD",
    },
    styles: [{
        where: "((SHIFT_ID != 1) AND (SHIFT_ID != 2))",
        polylineOptions: {
            strokeColor: "#FFFFFF",
            strokeWeight: "3"
        }
    }, {
        where: "SHIFT_ID = 1",
        polylineOptions: {
            strokeColor: "#FF0000",
            strokeWeight: "3"
        }
    }, {
        where: "SHIFT_ID = 2",
        polylineOptions: {
            strokeColor: "#ffbf00",
            strokeWeight: "3"
        }
    }]
});

proof of concept fiddle

代码段

var geocoder = new google.maps.Geocoder();
var map;

function initialize() {
  var map = new google.maps.Map(
    document.getElementById("map_canvas"), {
      center: new google.maps.LatLng(37.4419, -122.1419),
      zoom: 13,
      mapTypeId: google.maps.MapTypeId.ROADMAP
    });
  layer = new google.maps.FusionTablesLayer({
    map: map,
    heatmap: {
      enabled: false
    },
    query: {
      select: "geometry",
      from: "1D6d93-0iT2zUCw8IvkbpDPYDx2-jA0ZAWXi07mQD",
    },
    styles: [{
      where: "((SHIFT_ID != 1) AND (SHIFT_ID != 2))",
      polylineOptions: {
        strokeColor: "#FFFFFF",
        strokeWeight: "3"
      }
    }, {
      where: "SHIFT_ID = 1",
      polylineOptions: {
        strokeColor: "#FF0000",
        strokeWeight: "3"
      }
    }, {
      where: "SHIFT_ID = 2",
      polylineOptions: {
        strokeColor: "#ffbf00",
        strokeWeight: "3"
      }
    }]
  });
  geocoder.geocode({
    'address': "Winnipeg, Canada"
  }, function(results, status) {
    if (status === google.maps.GeocoderStatus.OK) {
      map.fitBounds(results[0].geometry.viewport);
    } else {
      alert('Geocode was not successful for the following reason: ' + status);
    }
  });
}
google.maps.event.addDomListener(window, "load", initialize);

html,
body,
#map_canvas {
  height: 100%;
  width: 100%;
  margin: 0px;
  padding: 0px
}

<script src="https://maps.googleapis.com/maps/api/js"></script>
<div id="map_canvas"></div>

＆＃34; WHERE＆＃34;在Google地图的Fusion Table Layer中忽略了子句

2 个答案: