diff --git a/src/backend/database.py b/src/backend/database.py
index 92f9367..512d889 100644
--- a/src/backend/database.py
+++ b/src/backend/database.py
@@ -10,6 +10,10 @@ from typing import Any, Dict, List, Optional, Tuple, Union
 from omegaconf import OmegaConf
 
 from src.backend.db import (
+    CREATE_ELSA_FILES_TABLE,
+    CREATE_ELSA_MEDIA_TABLE,
+    CREATE_ELSA_PROF_TABLE,
+    CREATE_ELSA_TABLE,
     CREATE_TABLE_APPARAT,
     CREATE_TABLE_APPKONTOS,
     CREATE_TABLE_FILES,
@@ -99,6 +103,10 @@ class Database:
         cursor.execute(CREATE_TABLE_PROF)
         cursor.execute(CREATE_TABLE_USER)
         cursor.execute(CREATE_TABLE_SUBJECTS)
+        cursor.execute(CREATE_ELSA_TABLE)
+        cursor.execute(CREATE_ELSA_PROF_TABLE)
+        cursor.execute(CREATE_ELSA_FILES_TABLE)
+        cursor.execute(CREATE_ELSA_MEDIA_TABLE)
         conn.commit()
         self.close_connection(conn)
 
@@ -129,7 +137,7 @@ class Database:
             one (bool, optional): Return the first result only. Defaults to False.
 
         Returns:
-            Union[Typle|List[Tuple]]: Returns the result of the query
+            Union[Tuple | List[Tuple]]: Returns the result of the query
         """
         conn = self.connect()
         cursor = conn.cursor()
@@ -648,6 +656,7 @@ class Database:
 
         Returns:
             list[tuple]: a list containing all the professors in individual tuples
+            tuple: (id, titel, fname, lname, fullname, mail, telnr)
         """
         return self.query_db("SELECT * FROM prof")
 
@@ -1196,3 +1205,134 @@ class Database:
             "UPDATE semesterapparat SET deletion_status=0, deleted_date=NULL WHERE appnr=?",
             (app_id,),
         )
+
+    # ELSA
+    def createElsaProf(self, name):
+        """create a new professor in the database for the ELSA system
+
+        Args:
+            name (str): the name of the professor
+        """
+        self.query_db("INSERT INTO elsa_prof (name) VALUES (?)", (name,))
+
+    def createElsaApparat(self, date, prof_id, semester):
+        """create a new apparat in the database for the ELSA system
+
+        Args:
+            date (str): the name of the apparat
+            prof_id (int): the id of the professor
+            semester (str): the semester the apparat is created in
+        """
+        self.query_db(
+            "INSERT INTO elsa (date, prof_id, semester) VALUES (?,?,?)",
+            (date, prof_id, semester),
+        )
+
+    def addElsaMedia(self, data: dict, elsa_id: int):
+        """add a media to the ELSA system
+
+        Args:
+            data (dict): a dictionary containing the data of the media,
+            Structured: {"chapter":str, "title":str, "signature":str, "pages":str}
+        """
+        self.query_db(
+            "INSERT INTO elsa_media (chapter, title, signature, pages, elsa_id) VALUES (?,?,?,?,?)",
+            (data["chapter"], data["title"], data["signature"], data["pages"], elsa_id),
+        )
+
+    def getElsaMedia(self, elsa_id: int):
+        """get all the media of an ELSA apparat
+
+        Args:
+            elsa_id (int): the id of the ELSA apparat
+
+        Returns:
+            list[tuple]: a list of tuples containing the media
+        """
+        return self.query_db("SELECT * FROM elsa_media WHERE elsa_id=?", (elsa_id,))
+
+    def insertElsaFile(self, file: list[dict], elsa_id: int):
+        """Instert a list of files into the ELSA system
+
+        Args:
+            file (list[dict]): a list containing all the files to be inserted
+            Structured: [{"name": "filename", "path": "path", "type": "filetype"}]
+            elsa_id (int): the id of the ELSA apparat
+        """
+        for f in file:
+            filename = f["name"]
+            path = f["path"]
+            filetyp = f["type"]
+            if path == "Database":
+                continue
+            blob = create_blob(path)
+            query = "INSERT OR IGNORE INTO elsa_files (filename, fileblob, elsa_id, filetyp) VALUES (?, ?, ?, ?)"
+            self.query_db(query, (filename, blob, elsa_id, filetyp))
+
+    def recreateElsaFile(self, filename: str, filetype: str) -> str:
+        """Recreate a file from the ELSA system
+
+        Args:
+            filename (str): the name of the file
+            elsa_id (int): the id of the ELSA apparat
+            filetype (str): the extension of the file to be created
+
+        Returns:
+            str: The filename of the recreated file
+        """
+        blob = self.query_db(
+            "SELECT fileblob FROM elsa_files WHERE filename=?", (filename,), one=True
+        )[0]
+        print(blob)
+        tempdir = config.database.tempdir
+        tempdir = tempdir.replace("~", str(Path.home()))
+        tempdir_path = Path(tempdir)
+        if not os.path.exists(tempdir_path):
+            os.mkdir(tempdir_path)
+        file = tempfile.NamedTemporaryFile(
+            delete=False, dir=tempdir_path, mode="wb", suffix=f".{filetype}"
+        )
+        file.write(blob)
+        print("file created")
+        return file.name
+
+    def getElsaApparats(self):
+        """Get all the ELSA apparats in the database
+
+        Returns:
+            list[tuple]: a list of tuples containing the ELSA apparats
+        """
+        return self.query_db("SELECT * FROM elsa")
+
+    def getElsaId(self, prof, semester, date):
+        """get the id of an ELSA apparat based on the professor, semester and date
+
+        Args:
+            prof (str): the name of the professor
+            semester (str): the semester
+            date (str): the date of the apparat
+
+        Returns:
+            int: the id of the ELSA apparat
+        """
+        data = self.query_db(
+            "SELECT id FROM elsa WHERE prof_id=? AND semester=? AND date=?",
+            (prof, semester, date),
+            one=True,
+        )
+        if data is None:
+            return None
+        return data[0]
+
+    def getElsaFiles(self, elsa_id: int):
+        """get all the files of an ELSA apparat
+
+        Args:
+            elsa_id (int): the id of the ELSA apparat
+
+        Returns:
+            list[tuple]: a list of tuples containing the files
+        """
+        return self.query_db(
+            "SELECT filename, filetyp FROM elsa_files WHERE elsa_id=?", (elsa_id,)
+        )