[BAEL-3634] Code for Spark DataFrame article (#12039)

* [BAEL-3634] Code for Spark DataFrame article

* [BAEL-3634] Improve example data sample and sort aggregations

* [BAEL-3634] change column name for clarity

* [BAEL-3634] Update method name with  U.S english standard

Co-authored-by: uzma khan <uzma.khan@nominet.uk>

apache-spark/docker/docker-compose.yaml

@@ -0,0 +1,33 @@
+version: "3"
+
+services:
+    postgres:
+        image: postgres:12.3-alpine
+        restart: always
+        environment:
+            POSTGRES_PASSWORD: postgres
+            POSTGRES_USER: postgres
+        expose:
+            - 5432
+        ports:
+            - 5432:5432
+        command: -p 5432        
+        volumes:
+            - ./init.sql:/docker-entrypoint-initdb.d/init.sql
+#            - postgres:/var/lib/postgresql/data
+
+    pgadmin:
+        image: dpage/pgadmin4:4.23
+        environment:
+            PGADMIN_DEFAULT_EMAIL: admin@pgadmin.com
+            PGADMIN_DEFAULT_PASSWORD: password
+            PGADMIN_LISTEN_PORT: 80
+        ports:
+            - 15432:80
+        volumes:
+            - pgadmin:/var/lib/pgadmin
+        depends_on:
+            - postgres
+
+volumes:
+    pgadmin:

apache-spark/docker/init.sql

@@ -0,0 +1 @@
+CREATE DATABASE customerdb;