correctly named unique constraint

model/src/main/java/lcsb/mapviewer/model/security/Privilege.java

@@ -6,7 +6,7 @@ import java.util.Objects;
 import javax.persistence.*;
 
 @Entity
-@Table(uniqueConstraints = @UniqueConstraint(columnNames = { "type", "object_id" }))
+@Table(uniqueConstraints = @UniqueConstraint(columnNames = { "type", "objectId" }))
 public class Privilege implements Serializable {
 
   private static final long serialVersionUID = 1L;
@@ -18,7 +18,7 @@ public class Privilege implements Serializable {
   @Enumerated(EnumType.STRING)
   private PrivilegeType type;
 
-  private Integer objectId = -1;
+  private Integer objectId;
 
   public Privilege() {
   }
@@ -60,7 +60,7 @@ public class Privilege implements Serializable {
   }
 
   public boolean isObjectPrivilege() {
-    return objectId != -1;
+    return objectId != null;
   }
 
   public Integer getId() {