Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <h2>Case 1: Range query over array values</h2> <p>EDIT: i did the test using wrong values.</p> <p>As <a href="http://docs.mongodb.org/manual/reference/operators/#array" rel="nofollow">documentation explains</a>, using conditional operators over array values (AND implicit operator), only needs to match one condition to return the document.</p> <p>So, </p> <ul> <li>_id:1 matches $lte and $gte clauses: <strong>OK</strong></li> <li>_id:2 matches $lte and $gte clauses: <strong>OK</strong></li> <li>_id:3 matches only $lte (5 &lt; 10 and 1 &lt; 10) clause: <strong>NOT OK</strong> but works as intended as the documentation explains.</li> </ul> <p>If you need to filter using this range queries over the array values you have to wrap the values using objects, as follows:</p> <pre><code>db.test_col2.insert({values:[{v:1} ,{v:5 },{v:6} ,{v:8}]}) db.test_col2.insert({values:[{v:5 },{v:7} ,{v:8},{v:10 },{v:40} ,{v:1}]}) db.test_col2.insert({values: [{v:50} ,{v:60} ,{v:5} ,{v:1} ]}) db.test_col2.find({values: {$elemMatch:{v:{$lte:10, $gte:8}}} }) {"_id":ObjectId("51273098140d09d9105739b5"),"values":[{"v":1},{"v":5},{"v":6},{"v":8}]} {"_id":ObjectId("51273098140d09d9105739b6"),"values":[{"v":5},{"v":7},{"v":8},{"v":10},{"v":40},{"v":1}]} </code></pre> <p>If you want to use an index for this query, you can do it as follows:</p> <pre><code>db.test_col2.ensureIndex({"values.v":1}) db.test_col2.find({values: {$elemMatch:{v:{$lte:10, $gte:8}}} }).explain() { "cursor": "BtreeCursor values.v_1", "isMultiKey": true, ... } </code></pre> <h2>Case 2: Hitting the index using open ranges</h2> <p>As you can see this query hits the index as expected.</p> <pre><code>for(var i=0 ; i&lt;120000 ; i++) { ... db.test_col.insert({from: (Math.random()*100)%100, to: (Math.random()*100)%100}); ... } &gt; db.test_col.ensureIndex({from:1, to:1}) &gt; db.test_col.count() 120002 &gt; db.test_col.find({from:{$gte:3}, to:{$lt:60}}).explain() { "cursor" : "BtreeCursor from_1_to_1", "isMultiKey" : false, "n" : 69741, "nscannedObjects" : 69902, "nscanned" : 116563, "scanAndOrder" : false, "indexOnly" : false, "nYields" : 0, "nChunkSkips" : 0, "millis" : 340, "indexBounds" : { "from" : [ [ 3, 1.7976931348623157e+308 ] ], "to" : [ [ -1.7976931348623157e+308, 60 ] ] }, "server" : "new-host-2.home:27017" } </code></pre>
    singulars
    1. This table or related slice is empty.
    1. POMongoDb: Search value in ranges in different situations
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USSamuel García
    1. USSamuel García
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COYes, we talking about 2.2. In Case 1, if you insert in second record 0 value - query return both records. In case 2, 340ms for 120000 records to slow. In my case, table have 2,500,000 records and it take about 10sec.
      singulars
      1. PO
      1. USEsp
    2. COThe queries you are talking about are the real queries? Or you just simplified it to explain your problem? I said this because i executed your queries locally and get the expected behaviour, as i said in my post.
      singulars
      1. PO
      1. USSamuel García
    3. COYes, simplified. But look at my answer with your example.
      singulars
      1. PO
      1. USEsp
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload