title: Duplicate key error with SonarQube 5.2
body: <p>I've been trying out SonarQube 5.2, but I'm getting errors such as these:</p>
  
  <pre><code>org.apache.ibatis.exceptions.PersistenceException: 
  ### Error updating database.  
  Cause:com.microsoft.sqlserver.jdbc.SQLServerException: Cannot insert duplicate key row in object 'dbo.projects' with unique index 'projects_uuid'. The duplicate key value is (AVDTnvuxTcMzGBo2P2Fw).
  ### The error may involve org.sonar.db.component.ComponentMapper.insert-Inline
  ### The error occurred while setting parameters
  ### Cause: com.microsoft.sqlserver.jdbc.SQLServerException: Cannot insert duplicate key row in object 'dbo.projects' with unique index 'projects_uuid'. The duplicate key value is (AVDTnvuxTcMzGBo2P2Fw).
  at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:26) ~[mybatis-3.2.7.jar:3.2.7]
  at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:154) ~[mybatis-3.2.7.jar:3.2.7]
  at org.apache.ibatis.session.defaults.DefaultSqlSession.insert(DefaultSqlSession.java:141) ~[mybatis-3.2.7.jar:3.2.7]
  at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:51) ~[mybatis-3.2.7.jar:3.2.7]
  at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:52) ~[mybatis-3.2.7.jar:3.2.7]
  at com.sun.proxy.$Proxy65.insert(Unknown Source) ~[na:na]
  at org.sonar.db.component.ComponentDao.insert(ComponentDao.java:282) ~[sonar-db-5.2.jar:na]
  at org.sonar.server.computation.step.PersistComponentsStep$PersistComponentStepsVisitor.persistComponent(PersistComponentsStep.java:172) ~[sonar-server-5.2.jar:na]
  at org.sonar.server.computation.step.PersistComponentsStep$PersistComponentStepsVisitor.persistAndPopulateCache(PersistComponentsStep.java:164) ~[sonar-server-5.2.jar:na]
  at org.sonar.server.computation.step.PersistComponentsStep$PersistComponentStepsVisitor.visitModule(PersistComponentsStep.java:130) ~[sonar-server-5.2.jar:na]
  at org.sonar.server.computation.component.PathAwareCrawler.visitNode(PathAwareCrawler.java:83) ~[sonar-server-5.2.jar:na]
  at org.sonar.server.computation.component.PathAwareCrawler.visit(PathAwareCrawler.java:51) ~[sonar-server-5.2.jar:na]
  at org.sonar.server.computation.component.PathAwareCrawler.visitChildren(PathAwareCrawler.java:71) ~[sonar-server-5.2.jar:na]
  at org.sonar.server.computation.component.PathAwareCrawler.visit(PathAwareCrawler.java:54) ~[sonar-server-5.2.jar:na]
  at org.sonar.server.computation.step.PersistComponentsStep.execute(PersistComponentsStep.java:77) ~[sonar-server-5.2.jar:na]
  at org.sonar.server.computation.step.ComputationStepExecutor.execute(ComputationStepExecutor.java:39) ~[sonar-server-5.2.jar:na]
  at org.sonar.server.computation.taskprocessor.report.ReportTaskProcessor.process(ReportTaskProcessor.java:53) ~[sonar-server-5.2.jar:na]
  at org.sonar.server.computation.taskprocessor.CeWorkerRunnableImpl.executeTask(CeWorkerRunnableImpl.java:78) [sonar-server-5.2.jar:na]
  at org.sonar.server.computation.taskprocessor.CeWorkerRunnableImpl.run(CeWorkerRunnableImpl.java:55) [sonar-server-5.2.jar:na]
  at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [na:1.8.0_45]
  at java.util.concurrent.FutureTask.runAndReset(Unknown Source) [na:1.8.0_45]
  at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(Unknown Source) [na:1.8.0_45]
  at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source) [na:1.8.0_45]
  at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [na:1.8.0_45]
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [na:1.8.0_45]
  at java.lang.Thread.run(Unknown Source) [na:1.8.0_45]
  </code></pre>
  
  <p>This only occurs if the solution I'm trying to analyse has more than one project. The same projects analyze just fine with SonarQube 5.1.2. I have the following configuration:</p>
  
  <ul>
  <li>SonarQube 5.2 (with a SQL Server 2012 database)</li>
  <li>C# 4.3</li>
  <li>Java 3.7</li>
  <li>LDAP 1.5</li>
  <li>Git 1.1</li>
  <li>SVN 1.2</li>
  <li>JavaScript 2.8</li>
  </ul>
  
  <p>Anyone else ran into this problem?</p>