arangodb/Documentation/Examples/geoIndexSortOptimization.ge...

arangosh&gt; db.geoSort.ensureIndex({ <span class="hljs-attr">type</span>: <span class="hljs-string">"geo"</span>, <span class="hljs-attr">fields</span>: [ <span class="hljs-string">"latitude"</span>, <span class="hljs-string">"longitude"</span> ] });
{
  <span class="hljs-string">"bestIndexedLevel"</span> : <span class="hljs-number">17</span>,
  <span class="hljs-string">"fields"</span> : [
    <span class="hljs-string">"latitude"</span>,
    <span class="hljs-string">"longitude"</span>
  ],
  <span class="hljs-string">"geoJson"</span> : <span class="hljs-literal">false</span>,
  <span class="hljs-string">"id"</span> : <span class="hljs-string">"geoSort/86143"</span>,
  <span class="hljs-string">"isNewlyCreated"</span> : <span class="hljs-literal">true</span>,
  <span class="hljs-string">"maxNumCoverCells"</span> : <span class="hljs-number">8</span>,
  <span class="hljs-string">"name"</span> : <span class="hljs-string">"idx_1646382083762814978"</span>,
  <span class="hljs-string">"sparse"</span> : <span class="hljs-literal">true</span>,
  <span class="hljs-string">"type"</span> : <span class="hljs-string">"geo"</span>,
  <span class="hljs-string">"unique"</span> : <span class="hljs-literal">false</span>,
  <span class="hljs-string">"worstIndexedLevel"</span> : <span class="hljs-number">4</span>,
  <span class="hljs-string">"code"</span> : <span class="hljs-number">201</span>
}
arangosh&gt; <span class="hljs-keyword">for</span> (i = <span class="hljs-number">-90</span>;  i &lt;= <span class="hljs-number">90</span>;  i += <span class="hljs-number">10</span>) {
........&gt;     <span class="hljs-keyword">for</span> (j = <span class="hljs-number">-180</span>; j &lt;= <span class="hljs-number">180</span>; j += <span class="hljs-number">10</span>) {
........&gt;         db.geoSort.save({ <span class="hljs-attr">name</span> : <span class="hljs-string">"Name/"</span> + i + <span class="hljs-string">"/"</span> + j, <span class="hljs-attr">latitude</span> : i, <span class="hljs-attr">longitude</span> : j });
........&gt;     }
........&gt; }
arangosh&gt; <span class="hljs-keyword">var</span> query = <span class="hljs-string">"FOR doc in geoSort SORT DISTANCE(doc.latitude, doc.longitude, 0, 0) LIMIT 5 RETURN doc"</span>
arangosh&gt; db._explain(query, {}, {<span class="hljs-attr">colors</span>: <span class="hljs-literal">false</span>});
Query <span class="hljs-built_in">String</span> (<span class="hljs-number">86</span> chars, <span class="hljs-attr">cacheable</span>: <span class="hljs-literal">true</span>):
 FOR doc <span class="hljs-keyword">in</span> geoSort SORT DISTANCE(doc.latitude, doc.longitude, <span class="hljs-number">0</span>, <span class="hljs-number">0</span>) LIMIT <span class="hljs-number">5</span> RETURN doc

Execution plan:
 Id   NodeType        Est.   Comment
  <span class="hljs-number">1</span>   SingletonNode      <span class="hljs-number">1</span>   * ROOT
  <span class="hljs-number">7</span>   IndexNode        <span class="hljs-number">703</span>     - FOR doc IN geoSort   <span class="hljs-comment">/* geo index scan */</span>
  <span class="hljs-number">5</span>   LimitNode          <span class="hljs-number">5</span>       - LIMIT <span class="hljs-number">0</span>, <span class="hljs-number">5</span>
  <span class="hljs-number">6</span>   ReturnNode         <span class="hljs-number">5</span>       - RETURN doc

Indexes used:
 By   Name                      Type   Collection   Unique   Sparse   Selectivity   Fields                        Ranges
  <span class="hljs-number">7</span>   idx_1646382083762814978   geo    geoSort      <span class="hljs-literal">false</span>    <span class="hljs-literal">true</span>             n/a   [ <span class="hljs-string">`latitude`</span>, <span class="hljs-string">`longitude`</span> ]   (GEO_DISTANCE([ <span class="hljs-number">0</span>, <span class="hljs-number">0</span> ], [ doc.<span class="hljs-string">`longitude`</span>, doc.<span class="hljs-string">`latitude`</span> ]) &lt; <span class="hljs-string">"unlimited"</span>)

Optimization rules applied:
 Id   RuleName
  <span class="hljs-number">1</span>   geo-index-optimizer
  <span class="hljs-number">2</span>   remove-unnecessary-calculations<span class="hljs-number">-2</span>


arangosh&gt; db._query(query);
[
  {
    <span class="hljs-string">"_key"</span> : <span class="hljs-string">"86849"</span>,
    <span class="hljs-string">"_id"</span> : <span class="hljs-string">"geoSort/86849"</span>,
    <span class="hljs-string">"_rev"</span> : <span class="hljs-string">"_ZXF6fFi--G"</span>,
    <span class="hljs-string">"name"</span> : <span class="hljs-string">"Name/0/0"</span>,
    <span class="hljs-string">"latitude"</span> : <span class="hljs-number">0</span>,
    <span class="hljs-string">"longitude"</span> : <span class="hljs-number">0</span>
  },
  {
    <span class="hljs-string">"_key"</span> : <span class="hljs-string">"86923"</span>,
    <span class="hljs-string">"_id"</span> : <span class="hljs-string">"geoSort/86923"</span>,
    <span class="hljs-string">"_rev"</span> : <span class="hljs-string">"_ZXF6fGC--C"</span>,
    <span class="hljs-string">"name"</span> : <span class="hljs-string">"Name/10/0"</span>,
    <span class="hljs-string">"latitude"</span> : <span class="hljs-number">10</span>,
    <span class="hljs-string">"longitude"</span> : <span class="hljs-number">0</span>
  },
  {
    <span class="hljs-string">"_key"</span> : <span class="hljs-string">"86851"</span>,
    <span class="hljs-string">"_id"</span> : <span class="hljs-string">"geoSort/86851"</span>,
    <span class="hljs-string">"_rev"</span> : <span class="hljs-string">"_ZXF6fFm---"</span>,
    <span class="hljs-string">"name"</span> : <span class="hljs-string">"Name/0/10"</span>,
    <span class="hljs-string">"latitude"</span> : <span class="hljs-number">0</span>,
    <span class="hljs-string">"longitude"</span> : <span class="hljs-number">10</span>
  },
  {
    <span class="hljs-string">"_key"</span> : <span class="hljs-string">"86775"</span>,
    <span class="hljs-string">"_id"</span> : <span class="hljs-string">"geoSort/86775"</span>,
    <span class="hljs-string">"_rev"</span> : <span class="hljs-string">"_ZXF6fFG--A"</span>,
    <span class="hljs-string">"name"</span> : <span class="hljs-string">"Name/-10/0"</span>,
    <span class="hljs-string">"latitude"</span> : <span class="hljs-number">-10</span>,
    <span class="hljs-string">"longitude"</span> : <span class="hljs-number">0</span>
  },
  {
    <span class="hljs-string">"_key"</span> : <span class="hljs-string">"86847"</span>,
    <span class="hljs-string">"_id"</span> : <span class="hljs-string">"geoSort/86847"</span>,
    <span class="hljs-string">"_rev"</span> : <span class="hljs-string">"_ZXF6fFi--E"</span>,
    <span class="hljs-string">"name"</span> : <span class="hljs-string">"Name/0/-10"</span>,
    <span class="hljs-string">"latitude"</span> : <span class="hljs-number">0</span>,
    <span class="hljs-string">"longitude"</span> : <span class="hljs-number">-10</span>
  }
]
[object ArangoQueryCursor, <span class="hljs-attr">count</span>: <span class="hljs-number">5</span>, <span class="hljs-attr">cached</span>: <span class="hljs-literal">false</span>, <span class="hljs-attr">hasMore</span>: <span class="hljs-literal">false</span>]