diff --git a/server.js b/server.js
index 90f8014..222272d 100644
--- a/server.js
+++ b/server.js
@@ -29,7 +29,7 @@ app.use(express.static(__dirname));
 // Helper to run the schema isolation command
 async function setSchema(client) {
   const schema = process.env.DB_SCHEMA || 'wind_projekt_bwscheddebrock';
-  await client.query(`set search_path to ${schema}, public;`);
+  await client.query(`SET search_path TO "${schema}", public;`);
 }
 
 // Database Initial Setup / Migration Logic Removed
@@ -46,21 +46,23 @@ app.get('/api/owners', async (req, res) => {
   try {
     await setSchema(client);
     
-    // Pure lowercase SQL without quotes on identifiers, using aliases for frontend
+    // Strict Case-Sensitivity Mapping based on server structure
     const query = `
-      select 
+      SELECT 
         id, 
-        nachname as "Nachname", 
-        vorname as "Vorname", 
-        ort as "Ort", 
-        flur as "Flur", 
-        flurstueck as "Flurstueck", 
-        gemarkung as "Gemarkung", 
-        status, 
-        notiz,
-        str_hnr as "Str_HNr",
-        st_asgeojson(st_transform(geom, 4326)) as geometry
-      from eigentuemerdaten
+        nachname AS "Nachname", 
+        vorname AS "Vorname", 
+        ort AS "Ort", 
+        "Flur" AS "Flur", 
+        "FlSt" AS "Flurstueck", 
+        "Gema" AS "Gemarkung", 
+        "PLZ" AS "PLZ",
+        "Land" AS "Land",
+        "AFlaeche" AS "AFlaeche",
+        status as "status", 
+        notiz as "notiz",
+        ST_AsGeoJSON(ST_Transform(geom, 4326)) as geometry
+      FROM eigentuemerdaten
     `;
     const result = await client.query(query);
     
@@ -91,11 +93,11 @@ app.get('/api/usage', async (req, res) => {
   try {
     await setSchema(client);
     const query = `
-      select 
+      SELECT 
         id,
-        nutzart,
-        st_asgeojson(st_transform(geom, 4326)) as geometry
-      from nutzung
+        "nutzart" as "nutzart",
+        ST_AsGeoJSON(ST_Transform(geom, 4326)) as geometry
+      FROM nutzung
     `;
     const result = await client.query(query);
     
@@ -125,11 +127,11 @@ app.get('/api/wea', async (req, res) => {
   try {
     await setSchema(client);
     const query = `
-      select 
+      SELECT 
         id, 
-        name as "Name",
-        st_asgeojson(st_transform(geom, 4326)) as geometry
-      from wea
+        "Name" AS "Name",
+        ST_AsGeoJSON(ST_Transform(geom, 4326)) as geometry
+      FROM wea
     `;
     const result = await client.query(query);
     
@@ -158,10 +160,10 @@ app.get('/api/infrastructure', async (req, res) => {
   try {
     await setSchema(client);
     const query = `
-      select 
+      SELECT 
         id, 
-        st_asgeojson(st_transform(geom, 4326)) as geometry
-      from infrastruktur
+        ST_AsGeoJSON(ST_Transform(geom, 4326)) as geometry
+      FROM infrastruktur
     `;
     const result = await client.query(query);
     
@@ -190,11 +192,11 @@ app.get('/api/variants', async (req, res) => {
   try {
     await setSchema(client);
     const query = `
-      select 
-        id, name, variante as "Variante",
-        st_asgeojson(st_transform(st_setsrid(geom, 25832), 4326)) as geometry
-      from kabeltrasse
-      order by id desc
+      SELECT 
+        id, name, "Variante" AS "Variante",
+        ST_AsGeoJSON(ST_Transform(ST_SetSRID(geom, 25832), 4326)) as geometry
+      FROM kabeltrasse
+      ORDER BY id DESC
     `;
     const result = await client.query(query);
     
@@ -233,19 +235,18 @@ app.post('/api/variants', async (req, res) => {
     const varianteValue = properties.Variante || (properties.name ? properties.name.replace('Variante ', '') : 'A');
     const geoJsonStr = JSON.stringify(geometry);
 
-    // Save with pure lowercase identifiers
     const upsertQuery = `
-      insert into kabeltrasse (geom, name, variante)
-      values (
-        st_makevalid(st_transform(st_setsrid(st_geomfromgeojson($1), 4326), 25832)), 
+      INSERT INTO kabeltrasse (geom, name, "Variante")
+      VALUES (
+        ST_MakeValid(ST_Transform(ST_SetSRID(ST_GeomFromGeoJSON($1), 4326), 25832)), 
         $2, 
         $3
       )
-      on conflict (variante) 
-      do update set 
-        geom = excluded.geom,
-        name = excluded.name
-      returning id
+      ON CONFLICT ("Variante") 
+      DO UPDATE SET 
+        geom = EXCLUDED.geom,
+        name = EXCLUDED.name
+      RETURNING id
     `;
     
     const upsertRes = await client.query(upsertQuery, [geoJsonStr, routeName, varianteValue]);
@@ -266,10 +267,10 @@ app.patch('/api/owners/:id', async (req, res) => {
   try {
     await setSchema(client);
     const query = `
-      update eigentuemerdaten
-      set status = $1, notiz = $2
-      where id = $3
-      returning id;
+      UPDATE eigentuemerdaten
+      SET status = $1, notiz = $2
+      WHERE id = $3
+      RETURNING id;
     `;
     const result = await client.query(query, [status, notiz, id]);
     if (result.rowCount === 0) return res.status(404).json({ error: 'Owner not found' });