Create Topic kafka-topics --create --bootstrap-server localhost:9092 --replication-factor 1 --partitions 1 --topic COUNTRY-CSV Create Table ksql> CREATE TABLE COUNTRYTABLE (countrycode VARCHAR PRIMARY KEY, countryname VARCHAR) WITH (KAFKA_TOPIC='COUNTRY-CSV', VALUE_FORMAT='DELIMITED'); Message --------------- Table created --------------- ksql> show tables; Table Name | Kafka Topic | Key…

I’ll further enhance this to use scenario from here: https://prateek-ashtikar512.medium.com/java-ksqldb-create-stream-with-json-7a22ccbecafa Link for reference — https://docs.ksqldb.io/en/latest/reference/#scalar-functions I hope you’ve already created USERPROFILE topic and users_stream streams kafka-topics --create --bootstrap-server localhost:9092 --replication-factor 1 --partitions 1 --topic USERPROFILE Created topic USERPROFILE.

In this example, we’ll see how to create Json stream and get the data. Create Topic kafka-topics --create --bootstrap-server localhost:9092 --replication-factor 1 --partitions 1 --topic USERPROFILE Created topic USERPROFILE. Create Stream ksql> CREATE STREAM userprofile (userid INT, firstname VARCHAR, lastname VARCHAR, countrycode VARCHAR, rating DOUBLE) WITH (VALUE_FORMAT = 'JSON', KAFKA_TOPIC…

Starting with ksqlDB 0.11.0, the executeStatement() method enables client apps to: Create new ksqlDB streams and tables Drop existing ksqlDB streams and tables Create new persistent queries, i.e., CREATE ... AS SELECT and INSERT INTO ... AS SELECT statements Pause, Resume, and Terminate persistent queries To use this method, pass…

In this example, we’ll learn how to insert a new row into a stream (insertInto()). Client apps can insert a new row of data into an existing ksqlDB stream by using the insertInto() method. To insert multiple rows in a streaming fashion, see streamInserts() instead. Rows for insertion are represented…

In this example, I will show you how to fetch data from KSQLDB using Java App using single batch (executeQuery()). I will use the Kafka topic and will create stream which will linked to this topic to get the source of data. You can refer for more details: https://docs.ksqldb.io/en/latest/developer-guide/ksqldb-clients/java-client/ Receive query results in a single batch (executeQuery()) The…

In this example, I will show you how to fetch data from KSQLDB using Java App using Synchronous Usage. I will use the Kafka topic and will create stream which will linked to this topic to get the source of data. You can refer for more details: https://docs.ksqldb.io/en/latest/developer-guide/ksqldb-clients/java-client/ Synchronous Usage¶ To consume…

Serial Threaded vs Multi-threaded - — Multi-threaded applications normally do parallel processing of tasks where as single threaded applications do one task at a time i.e. If there are two tasks such as T1, T2 they are executed in serial order i.e T1 after T2 or T2 after T1, where as multi threading enables us to…

This example demonstrates, using the high-level KStream DSL, how to implement the WordCount program that computes a simple word occurrence histogram from an input text. This example uses lambda expressions and thus works with Java 8+ only. In this example, the input stream reads from a topic named “streams-plaintext-input”, where…