3 files changed, 24 insertions, 16 deletions
diff --git a/src/org/traccar/web/server/model/DataServiceImpl.java b/src/org/traccar/web/server/model/DataServiceImpl.java
index 0b2a80ba..fa7a42d8 100644
--- a/src/org/traccar/web/server/model/DataServiceImpl.java
+++ b/src/org/traccar/web/server/model/DataServiceImpl.java
@@ -195,8 +195,8 @@ public class DataServiceImpl extends RemoteServiceServlet implements DataService
         User user = getUser();
         if (!user.getDevices().isEmpty()) {
             TypedQuery<Position> query = entityManager.createQuery(
-                    "SELECT x FROM Position x WHERE (x.device, x.time) IN (" +
-                            "SELECT y.device, MAX(y.time) FROM Position y WHERE y.device IN :devices GROUP BY y.device)", Position.class);
+                    "SELECT x FROM Position x WHERE x.id IN (" +
+                            "SELECT y.latestPosition FROM Device y WHERE y IN (:devices))", Position.class);
             query.setParameter("devices", user.getDevices());
             positions.addAll(query.getResultList());
         }
diff --git a/src/org/traccar/web/shared/model/Device.java b/src/org/traccar/web/shared/model/Device.java
index df4afb4b..d638046e 100644
--- a/src/org/traccar/web/shared/model/Device.java
+++ b/src/org/traccar/web/shared/model/Device.java
@@ -21,6 +21,7 @@ import javax.persistence.Column;
 import javax.persistence.Entity;
 import javax.persistence.GeneratedValue;
 import javax.persistence.Id;
+import javax.persistence.OneToOne;
 import javax.persistence.Table;
 
 @Entity
@@ -46,6 +47,13 @@ public class Device implements Serializable {
         return id;
     }
 
+    @OneToOne
+    private Position latestPosition;
+
+    public Position getLatestPosition() {
+        return latestPosition;
+    }
+
     @Column(unique = true)
     private String uniqueId;
 
diff --git a/src/org/traccar/web/shared/model/Position.java b/src/org/traccar/web/shared/model/Position.java
index 581c94c4..d5fa9a91 100644
--- a/src/org/traccar/web/shared/model/Position.java
+++ b/src/org/traccar/web/shared/model/Position.java
@@ -75,45 +75,45 @@ public class Position implements Serializable, Cloneable {
         return time;
     }
 
-    private boolean valid;
+    private Boolean valid;
 
-    public boolean getValid() {
+    public Boolean getValid() {
         return valid;
     }
 
-    private double latitude;
+    private Double latitude;
 
-    public double getLatitude() {
+    public Double getLatitude() {
         return latitude;
     }
 
-    private double longitude;
+    private Double longitude;
 
-    public double getLongitude() {
+    public Double getLongitude() {
         return longitude;
     }
 
-    private double altitude;
+    private Double altitude;
 
-    public double getAltitude() {
+    public Double getAltitude() {
         return altitude;
     }
 
-    private double speed;
+    private Double speed;
 
-    public double getSpeed() {
+    public Double getSpeed() {
         return speed;
     }
 
-    private double course;
+    private Double course;
 
-    public double getCourse() {
+    public Double getCourse() {
         return course;
     }
 
-    private double power;
+    private Double power;
 
-    public double getPower() {
+    public Double getPower() {
         return power;
     }