[ 
https://issues.apache.org/jira/browse/FLINK-31665?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17730003#comment-17730003
 ] 

Sergey Nuyanzin edited comment on FLINK-31665 at 6/7/23 8:37 AM:
-----------------------------------------------------------------

To be honest there is no 100% consistency across vendors.
e.g., as it was mentioned above {{ARRAY_CAT}} for snowflake and postgres

also {{ARRAY_CONCAT}} for e.g. BigQuery[1] and ClickHouse[2], DuckDB[3]
however the main difference is that these 3 vendors allow to concat arbitrary 
number of arrays not just 2 (while {{ARRAY_CAT}} for mentioned above is limited 
to 2 args)

Regarding your question [~twalthr]
{quote}
do we have already other functions containing `CONCAT`
{quote}
there is already existing {{CONCAT}} function to concatenate strings.
And it also allows to concatenate arbitrary number(>=2) of strings.

To be consistent doesn't it make sense to go same way as BigQuery, ClickHouse, 
DuckDB

like
{code:sql}
SELECT array_concat(array1, array2, ...);
{code}
?
[1] 
https://cloud.google.com/bigquery/docs/reference/standard-sql/array_functions#array_concat
[2] 
https://clickhouse.com/docs/en/sql-reference/functions/array-functions#arrayconcat
[3] https://duckdb.org/docs/sql/functions/nested.html


was (Author: sergey nuyanzin):
To be honest there is no 100% consistency across vendors.
e.g., as it was mentioned above {{ARRAY_CAT}} for snowflake and postgres

also {{ARRAY_CONCAT}} for e.g. BigQuery[1] and ClickHouse[2], DuckDB[3]
however the main difference is that these 3 vendors allow to concat arbitrary 
number of arrays not just 2 (while {{ARRAY_CAT}} for mentioned above is limited 
to 2 args)

[1] 
https://cloud.google.com/bigquery/docs/reference/standard-sql/array_functions#array_concat
[2] 
https://clickhouse.com/docs/en/sql-reference/functions/array-functions#arrayconcat
[3] https://duckdb.org/docs/sql/functions/nested.html

> Add ARRAY_CONCAT supported in SQL & Table API
> ---------------------------------------------
>
>                 Key: FLINK-31665
>                 URL: https://issues.apache.org/jira/browse/FLINK-31665
>             Project: Flink
>          Issue Type: Improvement
>          Components: Table SQL / Planner
>    Affects Versions: 1.18.0
>            Reporter: jackylau
>            Assignee: Hanyu Zheng
>            Priority: Major
>              Labels: pull-request-available
>             Fix For: 1.18.0
>
>




--
This message was sent by Atlassian Jira
(v8.20.10#820010)

Reply via email to