DEVX-2298: address how nulls are handled in ksqlDB; DEVX-2310: rename ksqlDB query

docs/index.rst

@@ -102,7 +102,7 @@ It generates the keys and certificates, brings up the Docker containers, and con
 You can run it with optional settings:
 
 - ``CLEAN``: controls whether certificates and the locally built |kconnect| image are regenerated in between runs
-- ``C3_KSQLDB_HTTPS``: sets |c3| and ksqlDB server to use ``HTTP`` or ``HTTPS`` (default: ``HTTP``)
+- ``C3_KSQLDB_HTTPS``: controls whether |c3| and ksqlDB server use ``HTTP``, if parameter is false, or ``HTTPS``, if parameter is true (default: ``true`` for ``HTTP``)
 - ``VIZ``: enables Elasticsearch and Kibana (default: ``true``)
 
 #. To run ``cp-demo`` the first time with defaults, run the following command. This takes a few minutes to complete.
@@ -199,14 +199,17 @@ Log into |c3|
    - Chrome: click on ``Advanced`` and when the window expands, click on ``Proceed to localhost (unsafe)``.
 
      .. figure:: images/c3-chrome-cert-warning.png
+        :width: 500px
 
    - Safari: open a new private browsing window (``Shift + ⌘ + N``), click on ``Show Details`` and when the window expands, click on ``visit this website``.
 
      .. figure:: images/c3-safari-cert-warning.png
+        :width: 500px
 
 #. At the login screen, log into |c3| as ``superUser`` and password ``superUser``, which has super user access to the cluster. You may also log in as :devx-cp-demo:`other users|scripts//security/ldap_users` to learn how each user's view changes depending on their permissions.
 
    .. figure:: images/c3-login.png
+      :width: 500px
 
 
 Brokers 
@@ -215,10 +218,11 @@ Brokers
 #. Select the cluster named "Kafka Raleigh".
 
    .. figure:: images/cluster_raleigh.png
+      :width: 500px
 
 #. Click on "Brokers".
 
-#. View the status of the Brokers in the cluster:
+#. View the status of the brokers in the cluster:
 
    .. figure:: images/landing_page.png
 
@@ -366,19 +370,7 @@ Its embedded producer is configured to be idempotent, exactly-once in order sema
    .. figure:: images/ksql_properties.png
       :alt: image
 
-#. This example creates two streams ``EN_WIKIPEDIA_GT_1`` and ``EN_WIKIPEDIA_GT_1_COUNTS`` to demonstrate how ksqlDB windows work. ``EN_WIKIPEDIA_GT_1`` counts occurrences with a tumbling window, and for a given key it writes a `null` into the table on the first seen message.  The underlying Kafka topic for ``EN_WIKIPEDIA_GT_1`` does not filter out those nulls, but to send just the counts greater than one downstream, there is a separate Kafka topic for ``EN_WIKIPEDIA_GT_1_COUNTS`` which does filter out those nulls (e.g., the query has a clause ``where ROWTIME is not null``).  From the bash prompt, view those underlying Kafka topics.
-
-- View messages in the topic ``EN_WIKIPEDIA_GT_1`` (jump to offset 0/partition 0), and notice the nulls:
-
-  .. figure:: images/messages_in_EN_WIKIPEDIA_GT_1.png
-     :alt: image
-
-- For comparison, view messages in the topic ``EN_WIKIPEDIA_GT_1_COUNTS`` (jump to offset 0/partition 0), and notice no nulls:
-
-  .. figure:: images/messages_in_EN_WIKIPEDIA_GT_1_COUNTS.png
-     :alt: image
-
-11. The `ksqlDB processing log <https://docs.confluent.io/current/ksql/docs/developer-guide/processing-log.html>`__ captures per-record errors during processing to help developers debug their ksqlDB queries. In this example, the processing log uses mutual TLS (mTLS) authentication, as configured in the custom :devx-cp-demo:`log4j properties file|scripts/helper/log4j-secure.properties`, to write entries into a Kafka topic. To see it in action, in the ksqlDB editor run the following "bad" query for 20 seconds:
+#. The `ksqlDB processing log <https://docs.confluent.io/current/ksql/docs/developer-guide/processing-log.html>`__ captures per-record errors during processing to help developers debug their ksqlDB queries. In this example, the processing log uses mutual TLS (mTLS) authentication, as configured in the custom :devx-cp-demo:`log4j properties file|scripts/helper/log4j-secure.properties`, to write entries into a Kafka topic. To see it in action, in the ksqlDB editor run the following "bad" query for 20 seconds:
 
 .. sourcecode:: bash
 
@@ -775,7 +767,6 @@ The security in place between |sr| and the end clients, e.g. ``appSA``, is as fo
 
        [
          "wikipedia.parsed.replica-value",
-         "EN_WIKIPEDIA_GT_1_COUNTS-value",
          "WIKIPEDIABOT-value",
          "EN_WIKIPEDIA_GT_1-value",
          "_confluent-ksql-ksql-clusterquery_CTAS_EN_WIKIPEDIA_GT_1_7-Aggregate-Aggregate-Materialize-changelog-value",

scripts/consumers/listen.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-for t in wikipedia.parsed WIKIPEDIABOT WIKIPEDIANOBOT EN_WIKIPEDIA_GT_1_COUNTS; do
+for t in wikipedia.parsed WIKIPEDIABOT WIKIPEDIANOBOT; do
 
   echo -e "\nSample message from Topic $t"
   docker exec connect kafka-avro-console-consumer --bootstrap-server kafka1:11091,kafka2:11092 \

scripts/helper/create-topics.sh

@@ -35,7 +35,7 @@ export KAFKA_LOG4J_OPTS="-Dlog4j.rootLogger=DEBUG,stdout -Dlog4j.logger.kafka=DE
    --partitions 2
 
 # Create Kafka topics with prefix WIKIPEDIA or EN_WIKIPEDIA, using ksqlDBUser principal
-for t in WIKIPEDIABOT WIKIPEDIANOBOT EN_WIKIPEDIA_GT_1 EN_WIKIPEDIA_GT_1_COUNTS
+for t in WIKIPEDIABOT WIKIPEDIANOBOT EN_WIKIPEDIA_GT_1
 do
   export KAFKA_LOG4J_OPTS="-Dlog4j.rootLogger=DEBUG,stdout -Dlog4j.logger.kafka=DEBUG,stdout" && kafka-topics \
      --bootstrap-server kafka1:11091 \

scripts/ksqlDB/statements.sql

@@ -3,4 +3,3 @@ CREATE STREAM wikipedianobot AS SELECT *, (length->new - length->old) AS BYTECHA
 CREATE STREAM wikipediabot AS SELECT *, (length->new - length->old) AS BYTECHANGE FROM wikipedia WHERE bot = true AND length IS NOT NULL AND length->new IS NOT NULL AND length->old IS NOT NULL;
 CREATE TABLE en_wikipedia_gt_1 AS SELECT user, meta->uri AS URI, count(*) AS COUNT FROM wikipedia WINDOW TUMBLING (size 300 second) WHERE meta->domain = 'commons.wikimedia.org' GROUP BY user, meta->uri HAVING count(*) > 1;
 CREATE STREAM en_wikipedia_gt_1_stream (USER string, URI string, COUNT bigint) WITH (kafka_topic='EN_WIKIPEDIA_GT_1', value_format='AVRO');
-CREATE STREAM en_wikipedia_gt_1_counts AS SELECT * FROM en_wikipedia_gt_1_stream where ROWTIME is not null;

scripts/start.sh

@@ -148,9 +148,8 @@ retry $MAX_WAIT host_check_ksqlDBserver_up || exit 1
 echo -e "\nRun ksqlDB queries (takes about 1 minute):"
 ${DIR}/ksqlDB/run_ksqlDB.sh
 
-echo -e "\nStart consumers for additional topics: WIKIPEDIANOBOT, EN_WIKIPEDIA_GT_1_COUNTS"
+echo -e "\nStart additional consumer for topic WIKIPEDIANOBOT"
 ${DIR}/consumers/listen_WIKIPEDIANOBOT.sh
-${DIR}/consumers/listen_EN_WIKIPEDIA_GT_1_COUNTS.sh
 
 echo
 echo