Initial ksqlDB launch docs

Documentation for ksqlDB at launch, plus subsequent bug fixes to 14 Jan 2020.

KSQL 5.0.0

This release brings a rich set of new features:

1. First class support for nested schemas through the STRUCT construct.
2. User defined scalar and aggregate functions. Annotate your java code, compile it, and drop the jar into a configurable directory, and your functions will be available to use within KSQL.
3. Stream-stream and table-table joins, in addition to Inner and outer joins.
4. A simpler way to secure KSQL applications with the prefixed ACLs available in Apache Kafka 2.0.0.

.. and more. Take a look at the release notes and the announcement blog for all the new features in this release.

Click here to download KSQL 5.0.0. As always, ping us on the #ksql channel on the community slack to leave feedback or ask questions about this release.

June Preview Release

The June preview includes the following new features:

• Support for STRUCT type in JSON and AVRO.
• UDF and UDAF support.
• Stream-Stream and Table-Table joins.
• Docker imaged for KSQL server and CLI.

KSQL May 2018 Preview Release

The May Preview release of the Confluent Platform brings several new features to KSQL, including support for inserting query results into existing streams, cleaning up Kafka topics and schemas, and Confluent Platform docker images for the CLI and Server.

• Download the KSQL May Preview as part of the latest Confluent Platform preview release.
• Read the announcement blog and the KSQL May Preview release notes for all the details.

Try it out and let us know what you think by filing issues or posting on the #ksql channel on Confluent Community Slack.

KSQL April 2018 Preview Release

The April Preview release of the Confluent Platform brings several new features to KSQL, including support for timestamps in more formats, aggregations for tables, and an improved REST API.

• Download the KSQL April Preview as part of the latest Confluent Platform preview release.
• Read the announcement blog and the KSQL April Preview release notes for all the details.

Try it out and let us know what you think by filing issues or posting on the #ksql channel on Confluent Community Slack.

KSQL 4.1

KSQL is now production ready.

• Download the KSQL 4.1 release. It is distributed as part of Confluent Platform 4.1.
• Our release blog has the details about what's new in this release.

KSQL January 2018 release

What's new

For a summary of what's new, please refer to the release blog post.

Change log

Full Changelog

Implemented enhancements:

• Enhance show topics; and print "topic"; #624 (bluemonk3y)
• Enhance 'print topic;' to display kafka topics #625
• EXTRACTJSONFIELD JSON array support #523
• Extend the DESCRIBE statement to more useful information #470
• Ksql server now generates a gc log #674 (apurvam)

Closed issues:

• KSQL Avro format seems to be incompatible with the avro format expected by Kafka connect. #651
• UDF function to search if the value exists in the json array #607

Merged pull requests:

• Make sure each Beacon ping includes current time #681 (apovzner)
  More informative help output for print-metrics #671 (rodesai)
• Cos integration for KSQL. #663 (hjafarpour)
• Remove suppression of method length check #662 (dguy)
• Allow passing a properties file to the quickstart examples #657 (mimaison)
• enable checkstyle check to avoid star import #654 (dguy)
• update datagen so iteration works properly and add schemas to use for testing #653 (dguy)
• Use PhoneHomeConfig for KSQL Beacon #648 (apovzner)
• updates for line length style check #645 (norwood)
• use EntityUtils instead of manually reading entity #644 (norwood)
• Add ksql-tools #634 (rodesai)
• Tests for cli module plus further tests for refactoring. #626 (dguy)
• [BUG] jsonNode array index access for EXTRACTJSONFIELD #610 (robert2d)
• [UDF] JSON Array Contains function #608 (satybald)
• [Minor] Fix Variable initialization #602 (satybald)

KSQL December Release

This tag represents the KSQL December release. For more information please refer to https://www.confluent.io/blog/ksql-december-release