diff -r 1574965c7dc7 -r 57cfb94ab99f src/main/java/de/uapcore/lightpit/dao/postgres/PGProjectDao.java
--- a/src/main/java/de/uapcore/lightpit/dao/postgres/PGProjectDao.java	Wed May 13 21:46:26 2020 +0200
+++ b/src/main/java/de/uapcore/lightpit/dao/postgres/PGProjectDao.java	Thu May 14 22:48:01 2020 +0200
@@ -28,7 +28,7 @@
  */
 package de.uapcore.lightpit.dao.postgres;
 
-import de.uapcore.lightpit.dao.AbstractDao;
+import de.uapcore.lightpit.dao.GenericDao;
 import de.uapcore.lightpit.dao.ProjectDao;
 import de.uapcore.lightpit.entities.Project;
 import de.uapcore.lightpit.entities.User;
@@ -37,18 +37,31 @@
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Objects;
 
-public final class PGProjectDao extends AbstractDao<Project> implements ProjectDao {
+import static de.uapcore.lightpit.dao.Functions.setForeignKeyOrNull;
+import static de.uapcore.lightpit.dao.Functions.setStringOrNull;
 
-    private final PGUserDao userDao;
+public final class PGProjectDao implements ProjectDao, GenericDao<Project> {
+
+    private final PreparedStatement insert, update, list, find;
 
-    private final PreparedStatement insert;
-    private final PreparedStatement update;
+    public PGProjectDao(Connection connection) throws SQLException {
+        list = connection.prepareStatement(
+                "select id, name, description, repourl, " +
+                        "userid, username, lastname, givenname, mail " +
+                        "from lpit_project " +
+                        "left join lpit_user owner on lpit_project.owner = owner.userid " +
+                        "order by name");
 
-    public PGProjectDao(Connection connection, PGUserDao userDao) throws SQLException {
-        super(connection.prepareStatement(
-                "select * from lpit_project join lpit_user owner on lpit_project.owner = owner.userid"));
+        find = connection.prepareStatement(
+                "select id, name, description, repourl, " +
+                        "userid, username, lastname, givenname, mail " +
+                        "from lpit_project " +
+                        "left join lpit_user owner on lpit_project.owner = owner.userid " +
+                        "where id = ?");
 
         insert = connection.prepareStatement(
                 "insert into lpit_project (name, description, repourl, owner) values (?, ?, ?, ?)"
@@ -56,17 +69,24 @@
         update = connection.prepareStatement(
                 "update lpit_project set name = ?, description = ?, repourl = ?, owner = ? where id = ?"
         );
-
-        this.userDao = userDao;
     }
 
-    @Override
-    public Project mapColumns(ResultSet result, String q) throws SQLException {
-        final var proj = new Project(result.getInt(qual(q, "id")));
-        proj.setName(result.getString(qual(q, "name")));
-        proj.setDescription(result.getString(qual(q, "description")));
-        proj.setRepoUrl(result.getString(qual(q, "repourl")));
-        proj.setOwner(userDao.mapColumns(result, "owner"));
+    public Project mapColumns(ResultSet result) throws SQLException {
+        final var proj = new Project(result.getInt("id"));
+        proj.setName(result.getString("name"));
+        proj.setDescription(result.getString("description"));
+        proj.setRepoUrl(result.getString("repourl"));
+
+        final int id = result.getInt("userid");
+        if (id != 0) {
+            final var user = new User(id);
+            user.setUsername(result.getString("username"));
+            user.setGivenname(result.getString("givenname"));
+            user.setLastname(result.getString("lastname"));
+            user.setMail(result.getString("mail"));
+            proj.setOwner(user);
+        }
+
         return proj;
     }
 
@@ -87,6 +107,30 @@
         setStringOrNull(update, 2, instance.getDescription());
         setStringOrNull(update, 3, instance.getRepoUrl());
         setForeignKeyOrNull(update, 4, instance.getOwner(), User::getUserID);
+        update.setInt(5, instance.getId());
         return update.executeUpdate() > 0;
     }
+
+    @Override
+    public List<Project> list() throws SQLException {
+        List<Project> projects = new ArrayList<>();
+        try (var result = list.executeQuery()) {
+            while (result.next()) {
+                projects.add(mapColumns(result));
+            }
+        }
+        return projects;
+    }
+
+    @Override
+    public Project find(int id) throws SQLException {
+        find.setInt(1, id);
+        try (var result = find.executeQuery()) {
+            if (result.next()) {
+                return mapColumns(result);
+            } else {
+                return null;
+            }
+        }
+    }
 }