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PORetrieving value from objectdb database from program
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copied!<p>I am facing some problems while I am trying to fetch data through the program. I am using objectDB as my database. Also, my database is already set up and I have dropped the laptop.odb file in the db folder of my objectDB installation. Also, when I go to the explorer and fire the query:</p> <p><code>select this.modelName == "HP Pavillion"</code></p> <p>correct results comes up. But, when I try to do the same thing with my code as in the following </p> <p><code>public static void main(String argv[]) {<br> PersistenceManager pm = Utilities.getPersistenceManager("laptop.odb"); System.out.println("-- TEST --\n");<br> Query query = pm.newQuery(Laptop.class,"this.modelName == \"HP Pavillion\""); Collection result = (Collection)query.execute(); System.out.println("Result is >> "+result); </code></p> <p>Here no results are returned. My output is :<br> -- TEST find --</p> <p>Result is >> []</p> <p>My code for the class is the following. </p> <pre><code> package com.project; import java.util.*; import javax.annotation.processing.Processor; import javax.jdo.*; import com.objectdb.Utilities; public class Laptop { String modelName; // key public static void main(String argv[]) { PersistenceManager pm = Utilities.getPersistenceManager("laptop.odb"); System.out.println("-- TEST find --\n"); Query query = pm.newQuery(Laptop.class,"this.modelName == \"HP Pavillion\""); Collection result = (Collection)query.execute(); System.out.println("Result is >> "+result); } </code></pre> <p>Any suggestions ?</p>

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