You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@calcite.apache.org by "Forward Xu (JIRA)" <ji...@apache.org> on 2019/02/25 15:03:00 UTC
[jira] [Closed] (CALCITE-2809) Add JSON_LENGTH function
[ https://issues.apache.org/jira/browse/CALCITE-2809?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Forward Xu closed CALCITE-2809.
-------------------------------
Resolution: Duplicate
> Add JSON_LENGTH function
> ------------------------
>
> Key: CALCITE-2809
> URL: https://issues.apache.org/jira/browse/CALCITE-2809
> Project: Calcite
> Issue Type: Improvement
> Reporter: Forward Xu
> Priority: Major
>
> {{JSON_LENGTH(*json_doc*[, *path*\])}}
> Returns the length of a JSON document, or, if a _path_ argument is given, the length of the value within the document identified by the path. Returns {{NULL}} if any argument is {{NULL}} or the _path_ argument does not identify a value in the document. An error occurs if the _json_doc_ argument is not a valid JSON document or the _path_ argument is not a valid path expression or contains a {{*}} or {{**}} wildcard.
> The length of a document is determined as follows:
> * The length of a scalar is 1.
> * The length of an array is the number of array elements.
> * The length of an object is the number of object members.
> * The length does not count the length of nested arrays or objects.
> SELECT JSON_LENGTH('[1, 2, \{"a": 3}]');
> +---------------------------------+
> | JSON_LENGTH('[1, 2, \{"a": 3}]') |
> +---------------------------------+
> | 3 |
> +---------------------------------+
> SELECT JSON_LENGTH('\{"a": 1, "b": {"c": 30}}');
> +-----------------------------------------+
> | JSON_LENGTH('\{"a": 1, "b": {"c": 30}}') |
> +-----------------------------------------+
> | 2 |
> +-----------------------------------------+
> SELECT JSON_LENGTH('\{"a": 1, "b": {"c": 30}}', '$.b');
> +------------------------------------------------+
> | JSON_LENGTH('\{"a": 1, "b": {"c": 30}}', '$.b') |
> +------------------------------------------------+
> | 1 |
> +------------------------------------------------+
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)