[
https://issues.apache.org/jira/browse/CALCITE-2871?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16777818#comment-16777818
]
Hongze Zhang commented on CALCITE-2871:
---------------------------------------
I've added the information about this function.
And this is a table function. The syntax described in the SQL standard seems to
be complicated, so I separated this one from CALCITE-2266. And I am afraid that
it will be a lot of work to do if we would like to provide a complete or
near-complete implementation.
> Implement JSON_TABLE table function
> -----------------------------------
>
> Key: CALCITE-2871
> URL: https://issues.apache.org/jira/browse/CALCITE-2871
> Project: Calcite
> Issue Type: Sub-task
> Reporter: Hongze Zhang
> Priority: Major
>
> Below is the syntax of JSON_TABLE published by ISO/IEC TR 19075-5[1]:
> {code}
> <JSON table> ::=
> JSON_TABLE <left paren>
> <JSON API common syntax>
> <JSON table columns clause>
> [ <JSON table plan clause> ]
> [ <JSON table error behavior> ON ERROR ]
> <right paren>
>
> <JSON table columns clause> ::=
> COLUMNS <left paren>
> <JSON table column definition>
> [ { <comma> <JSON table column definition> }... ]
> <right paren>
>
> <JSON table column definition> ::=
> <JSON table ordinality column definition>
> | <JSON table regular column definition>
> | <JSON table formatted column definition>
> | <JSON table nested columns>
> <JSON table ordinality column definition> ::=
> <column name> FOR ORDINALITY
>
> <JSON table regular column definition> ::=
> <column name> <data type>
> [ PATH <JSON table column path specification> ]
> [ <JSON table column empty behavior> ON EMPTY ]
> [ <JSON table column error behavior> ON ERROR ]
>
> <JSON table column empty behavior> ::=
> ERROR
> | NULL
> | DEFAULT <value expression>
>
> <JSON table column error behavior> ::=
> ERROR
> | NULL
> | DEFAULT <value expression>
>
> <JSON table column path specification> ::=
> <JSON path specification>
> <JSON table formatted column definition> ::=
> <column name> <data type>
> FORMAT <JSON representation>
> [ PATH <JSON table column path specification> ]
> [ <JSON table formatted column wrapper behavior> WRAPPER ]
> [ <JSON table formatted column quotes behavior> QUOTES
> [ ON SCALAR STRING ] ]
> [ <JSON table formatted column empty behavior> ON EMPTY ]
> [ <JSON table formatted column error behavior> ON ERROR ]
> <JSON table formatted column wrapper behavior> ::=
> WITHOUT [ ARRAY ]
> | WITH [ CONDITIONAL | UNCONDITIONAL ] [ ARRAY ]
>
> <JSON table formatted column quotes behavior> ::=
> KEEP
> | OMIT
>
> <JSON table formatted column empty behavior> ::=
> ERROR
> | NULL
> | EMPTY ARRAY
> | EMPTY OBJECT
>
> <JSON table formatted column error behavior> ::=
> ERROR
> | NULL
> | EMPTY ARRAY
> | EMPTY OBJECT
> <JSON table error behavior> ::=
> ERROR
> | EMPTY
> {code}
> A usage example:
> {code:sql}
> SELECT bookclub.id, jt.name, jt.type, jt.number
> FROM bookclub,
> JSON_TABLE ( bookclub.jcol, 'lax $'
> COLUMNS ( name VARCHAR(30) PATH 'lax $.Name',
> NESTED PATH 'lax $.phoneNumber[*]'
> COLUMNS ( type VARCHAR(10) PATH 'lax $.type',
> number CHAR(12) PATH 'lax
> $.number' )
> ) AS jt;
> {code}
> As another reference, Oracle has a non-standard implementation[2] of this
> function.
> [1]
> http://standards.iso.org/ittf/PubliclyAvailableStandards/c065143_ISO_IEC_TR_19075-5_2016.zip
> [2] https://docs.oracle.com/database/121/SQLRF/functions092.htm#SQLRF56973
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
