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POMongoDB $query operator ignores index?
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  1. POMongoDB $query operator ignores index?
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    copied!<p>I created a test MongoDB collection "sampleCollection" with documents which looks like:</p> <pre><code> "_id" : ObjectId("510929e041cb2179b41ace1c"), "stringField" : "Random string0", "longField" : NumberLong(886) </code></pre> <p>and has index on field "stringField". When I execute </p> <pre><code>db.sampleCollection.find({"stringField":"Random string0"}).explain() </code></pre> <p>everything is ok:</p> <pre><code> "cursor" : "BtreeCursor stringField_1", "isMultiKey" : false, "n" : 2, "nscannedObjects" : 2, "nscanned" : 2, "nscannedObjectsAllPlans" : 2, "nscannedAllPlans" : 2, "scanAndOrder" : false, "indexOnly" : false, "nYields" : 0, "nChunkSkips" : 0, "millis" : 0, "indexBounds" : { "stringField" : [ [ "Random string0", "Random string0" ] ] } </code></pre> <p>but </p> <pre><code>db.sampleCollection.find({$query:{"stringField":"Random string0"}}).explain() </code></pre> <p>gets me</p> <pre><code>"cursor" : "BasicCursor", "isMultiKey" : false, "n" : 0, "nscannedObjects" : 4, "nscanned" : 4, "nscannedObjectsAllPlans" : 4, "nscannedAllPlans" : 4, "scanAndOrder" : false, "indexOnly" : false, "nYields" : 0, "nChunkSkips" : 0, "millis" : 0, "indexBounds" : { } </code></pre> <p>This is not looks like a problem, but I'm using <strong>org.springframework.data.mongodb</strong> framework in production and usage of query constructions is an only way to write repositories. And thus I have a db which completely ignores indexed data.</p> <p>Is it correct? Or I misunderstood something?</p>
 

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