diff --git a/include/basis.class.php b/include/basis.class.php
index fe56eb05d..663cdaa6d 100644
--- a/include/basis.class.php
+++ b/include/basis.class.php
@@ -130,6 +130,6 @@ class basis
 	 */
 	public function convert_html_chars($value)
 	{
-		return htmlspecialchars($value);
+		return htmlspecialchars($value ?? '');
 	}
 }
diff --git a/include/basis_db.class.php b/include/basis_db.class.php
index d8d2ebaff..7205cf8bb 100644
--- a/include/basis_db.class.php
+++ b/include/basis_db.class.php
@@ -27,8 +27,8 @@ require_once(dirname(__FILE__).'/basis.class.php');
 
 abstract class db extends basis
 {
-	protected static $db_conn=null;
-	protected $db_result=null;
+	protected static $db_conn = null;
+	protected $db_result = null;
 	protected $debug=false;
 
 	function __construct()
@@ -46,18 +46,18 @@ abstract class db extends basis
 
 	abstract function db_connect();
 	abstract function db_query($sql);
-	abstract function db_fetch_object($result=null, $i=null);
-	abstract function db_fetch_array($result=null);
-	abstract function db_fetch_row($result=null, $i=null);
-	abstract function db_fetch_assoc($result=null, $i=null);
-	abstract function db_result($result = null, $i, $item);
-	abstract function db_num_rows($result=null);
-	abstract function db_num_fields($result=null);
-	abstract function db_field_name($result=null, $i);
-	abstract function db_affected_rows($result=null);
-	abstract function db_result_seek($result=null, $offset);
+	abstract function db_fetch_object($result = null, $i = null);
+	abstract function db_fetch_array($result = null);
+	abstract function db_fetch_row($result = null, $i = null);
+	abstract function db_fetch_assoc($result = null, $i = null);
+	abstract function db_result($result = null, $i = null, $item = null);
+	abstract function db_num_rows($result = null);
+	abstract function db_num_fields($result = null);
+	abstract function db_field_name($result = null, $i = null);
+	abstract function db_affected_rows($result = null);
+	abstract function db_result_seek($result = null, $offset = null);
 	abstract function db_last_error();
-	abstract function db_free_result($result=null);
+	abstract function db_free_result($result = null);
 	abstract function db_version();
 	abstract function db_escape($var);
 	abstract function db_null_value($var, $qoute=true);
diff --git a/include/datum.class.php b/include/datum.class.php
index 950cd60ff..8ead28aeb 100644
--- a/include/datum.class.php
+++ b/include/datum.class.php
@@ -356,7 +356,7 @@ class datum
 	 */
 	public function formatDatum($datum, $format='Y-m-d H:i:s', $strict=false)
 	{
-		if(trim($datum)=='')
+		if (trim($datum ?? '') == '')
 			return '';
 
 		$ts='';
diff --git a/include/lehrform.class.php b/include/lehrform.class.php
index f293ed065..3c5ca5d56 100644
--- a/include/lehrform.class.php
+++ b/include/lehrform.class.php
@@ -34,6 +34,8 @@ class lehrform extends basis_db
 	public $bezeichnung_kurz;
 	public $bezeichnung_lang;
 
+	public $lehrform_kurzbz;
+
 	/**
 	 * Konstruktor - Laedt optional eine Lehrform
 	 * @param $lehrform_kurbz Lehrform die geladen werden soll (default=null)
diff --git a/include/lehrveranstaltung.class.php b/include/lehrveranstaltung.class.php
index 26f846f8e..7fa21273b 100644
--- a/include/lehrveranstaltung.class.php
+++ b/include/lehrveranstaltung.class.php
@@ -655,27 +655,27 @@ class lehrveranstaltung extends basis_db
 	public function validate()
 	{
 		//Laenge Pruefen
-		if (mb_strlen($this->bezeichnung) > 128)
+		if (mb_strlen($this->bezeichnung ?? '') > 128)
 		{
 			$this->errormsg = 'Bezeichnung darf nicht laenger als 128 Zeichen sein';
 			return false;
 		}
-		if (mb_strlen($this->kurzbz) > 16)
+		if (mb_strlen($this->kurzbz ?? '') > 16)
 		{
 			$this->errormsg = 'Kurzbez darf nicht laenger als 16 Zeichen sein';
 			return false;
 		}
-		if (mb_strlen($this->anmerkung) > 64)
+		if (mb_strlen($this->anmerkung ?? '') > 64)
 		{
 			$this->errormsg = 'Anmerkung darf nicht laenger als 64 Zeichen sein';
 			return false;
 		}
-		if (mb_strlen($this->lehreverzeichnis) > 16)
+		if (mb_strlen($this->lehreverzeichnis ?? '') > 16)
 		{
 			$this->errormsg = 'Lehreverzeichnis darf nicht laenger als 16 Zeichen sein';
 			return false;
 		}
-		if (mb_strlen($this->lvnr) > 32)
+		if (mb_strlen($this->lvnr ?? '') > 32)
 		{
 			$this->errormsg = 'LVNR darf nicht laenger als 32 Zeichen sein';
 			return false;
diff --git a/include/lvangebot.class.php b/include/lvangebot.class.php
index 701d54ab7..1889ae4d0 100644
--- a/include/lvangebot.class.php
+++ b/include/lvangebot.class.php
@@ -40,6 +40,7 @@ class lvangebot extends basis_db
 	protected $anmeldefenster_start;	// timestamp
 	protected $anmeldefenster_ende;		// timestamp
 	protected $updateamum;				// timestamp
+	protected $updatenamum;
 	protected $updatevon;				// varchar(32)
 	protected $insertamum;				// timestamp
 	protected $insertvon;				// varchar(32)
diff --git a/include/organisationseinheit.class.php b/include/organisationseinheit.class.php
index b0b53284f..1f1ce84c3 100644
--- a/include/organisationseinheit.class.php
+++ b/include/organisationseinheit.class.php
@@ -49,6 +49,8 @@ class organisationseinheit extends basis_db
 	public $beschreibung;
 	public $oetyp_bezeichnung;
 
+	public $kurzzeichen;
+	public $freigabegrenze;
 
 	/**
 	 * Konstruktor
diff --git a/include/pgsql.class.php b/include/pgsql.class.php
index 92a6d0494..dae14e73d 100644
--- a/include/pgsql.class.php
+++ b/include/pgsql.class.php
@@ -44,7 +44,7 @@ class basis_db extends db
 
 	public function db_query($sql)
 	{
-		if ($this->db_result=pg_query(basis_db::$db_conn,$sql))
+		if ($this->db_result = @pg_query(basis_db::$db_conn,$sql))
 			return $this->db_result;
 		else
 		{
@@ -53,7 +53,7 @@ class basis_db extends db
 		}
 	}
 
-	public function db_num_rows($result=null)
+	public function db_num_rows($result = null)
 	{
 		if(is_null($result))
 			return pg_num_rows($this->db_result);
@@ -61,7 +61,7 @@ class basis_db extends db
 			return pg_num_rows($result);
 	}
 
-	public function db_fetch_object($result = null, $i=null)
+	public function db_fetch_object($result = null, $i = null)
 	{
 		if(is_null($result))
 		{
@@ -79,7 +79,7 @@ class basis_db extends db
 		}
 	}
 
-	public function db_fetch_row($result = null, $i=null)
+	public function db_fetch_row($result = null, $i = null)
 	{
 		if(is_null($result))
 		{
@@ -97,7 +97,7 @@ class basis_db extends db
 		}
 	}
 
-	public function db_fetch_assoc($result = null, $i=null)
+	public function db_fetch_assoc($result = null, $i = null)
 	{
 		if(is_null($result))
 		{
@@ -115,7 +115,7 @@ class basis_db extends db
 		}
 	}
 
-	public function db_result($result = null, $i,$item)
+	public function db_result($result = null, $i = null, $item = null)
 	{
 		if(is_null($result))
 		{
@@ -153,10 +153,10 @@ class basis_db extends db
 
 	public function db_last_error()
 	{
-		return pg_last_error();
+		return pg_last_error(basis_db::$db_conn);
 	}
 
-	public function db_affected_rows($result=null)
+	public function db_affected_rows($result = null)
 	{
 		if(is_null($result))
 			return pg_affected_rows($this->db_result);
@@ -164,7 +164,7 @@ class basis_db extends db
 			return pg_affected_rows($result);
 	}
 
-	public function db_result_seek($result=null, $offset)
+	public function db_result_seek($result = null, $offset = null)
 	{
 		if(is_null($result))
 			return pg_result_seek($this->db_result, $offset);
@@ -172,7 +172,7 @@ class basis_db extends db
 			return pg_result_seek($result, $offset);
 	}
 
-	public function db_fetch_array($result=null, $row=null, $result_type=PGSQL_NUM)
+	public function db_fetch_array($result = null, $row = null, $result_type=PGSQL_NUM)
 	{
 		if(is_null($result))
 			return pg_fetch_array($this->db_result, $row, $result_type);
@@ -180,7 +180,7 @@ class basis_db extends db
 			return pg_fetch_array($result, $row, $result_type);
 	}
 
-	public function db_num_fields($result=null)
+	public function db_num_fields($result = null)
 	{
 		if(is_null($result))
 			return pg_num_fields($this->db_result);
@@ -191,7 +191,7 @@ class basis_db extends db
 	/**
 	 * Liefert den Feldnamen mit index i
 	 */
-	public function db_field_name($result=null, $i)
+	public function db_field_name($result = null, $i = null)
 	{
 		if(is_null($result))
 			return pg_field_name($this->db_result, $i);
@@ -230,7 +230,7 @@ class basis_db extends db
 	 */
 	public function db_escape($var)
 	{
-		return pg_escape_string($var);
+		return pg_escape_string(basis_db::$db_conn, $var);
 	}
 
 	/**
diff --git a/include/studiengang.class.php b/include/studiengang.class.php
index 676ee97f3..060a5bd75 100644
--- a/include/studiengang.class.php
+++ b/include/studiengang.class.php
@@ -68,6 +68,11 @@ class studiengang extends basis_db
 	public $beschreibung;
 	public $studiengang_typ_arr = array(); 	// Array mit den Studiengangstypen
 
+	public $telefon;
+	public $aktiv;
+	public $beantragung;
+	public $lgart_biscode;
+
 	/**
 	 * Konstruktor
 	 * @param studiengang_kz Kennzahl des zu ladenden Studienganges
diff --git a/vilesci/lehre/lehrveranstaltung_details.php b/vilesci/lehre/lehrveranstaltung_details.php
index bad2a7d93..45908896d 100644
--- a/vilesci/lehre/lehrveranstaltung_details.php
+++ b/vilesci/lehre/lehrveranstaltung_details.php
@@ -210,7 +210,7 @@
 			<td>Kurzbz*</td>
 			<td><input type="text" name="kurzbz" '.($lv->lehrveranstaltung_id==''?'onchange="copyToLehreVz();"':'onchange="return copyToLehreVzAsk();"').' value="'.$lv->kurzbz.'" /></td>
 			<td>Bezeichnung*</td>
-			<td colspan=3><input type="text" name="bezeichnung" value="'.htmlentities($lv->bezeichnung, ENT_QUOTES, 'UTF-8').'" size="60" maxlength="128"></td>
+			<td colspan=3><input type="text" name="bezeichnung" value="'.htmlentities($lv->bezeichnung ?? '', ENT_QUOTES, 'UTF-8').'" size="60" maxlength="128"></td>
 		</tr>
 		<tr>
 			<td>Sprache</td>
@@ -226,7 +226,7 @@
 		}
 		$htmlstr .= '</select></td>
 			<td>Bezeichnung English</td>
-			<td colspan=3><input type="text" name="bezeichnung_english" value="'.htmlentities($lv->bezeichnung_english, ENT_QUOTES, 'UTF-8').'" size="60" maxlength="256"></td>
+			<td colspan=3><input type="text" name="bezeichnung_english" value="'.htmlentities($lv->bezeichnung_english ?? '', ENT_QUOTES, 'UTF-8').'" size="60" maxlength="256"></td>
 		</tr><tr>
 			<td>Studiengang</td>
 			<td><select name="studiengang_kz">';