Ksql: Support escaping identifier names.

Created on 31 Jan 2018 · 5Comments · Source: confluentinc/ksql

In standard SQL we can use escaped names for tables and columns. We should support this in KSQL too.

data-accessibility enhancement

Source

hjafarpour

👍7

Most helpful comment

First time trying to use KSQL and running directly into this issue. I discovered the undocumented backtick escaping, and then running into https://github.com/confluentinc/ksql/issues/1213. The actually working workaround if table columns are declared with backtick escaping and being uppercase:

CREATE STREAM stream1 (
`window` varchar,
`topic` varchar
) WITH (value_format='JSON');

ksql> select `window`, `topic` from stream1 limit 2;
null | null
null | null
LIMIT reached for the partition.
Query terminated

CREATE STREAM stream2 (
`WINDOW` varchar,
`TOPIC` varchar
) WITH (value_format='JSON');

ksql> select `WINDOW`, `TOPIC` from stream2 limit 2;
1528278435000 | testkafka4
1528278465000 | testkafka5
LIMIT reached for the partition.
Query terminated

My JSON contains "window" and "topic" fields in lower case

dtheodor on 13 Jun 2018

👍3

All 5 comments

This will enable using reserved keywords as column names, and increase the number of data streams ksql can work with.

apurvam on 14 Feb 2018

What's the current state of this issue?

big-andy-coates on 26 Apr 2018

CREATE STREAM stream1 (
`window` varchar,
`topic` varchar
) WITH (value_format='JSON');

ksql> select `window`, `topic` from stream1 limit 2;
null | null
null | null
LIMIT reached for the partition.
Query terminated

CREATE STREAM stream2 (
`WINDOW` varchar,
`TOPIC` varchar
) WITH (value_format='JSON');

ksql> select `WINDOW`, `TOPIC` from stream2 limit 2;
1528278435000 | testkafka4
1528278465000 | testkafka5
LIMIT reached for the partition.
Query terminated

My JSON contains "window" and "topic" fields in lower case

dtheodor on 13 Jun 2018

👍3

Experiencing the same. Verified 'workaroud'. Need to uppercase the field name and have it enclosed with backticks.

(Using version 5.1.0)

vdweij on 30 Jan 2019

Closing this ticket out in favor of the more specific issues described in other tickets - there has been a ton of work in recent KSQL versions (will be released in the next upcoming release) to address the quoted identifier issues. Feel free to open new issues with more specific information about the issues you are facing if the issues persist!