JSON_EACH_TEXT_OUTER

Description

The json_each_text_outer table function expands the top-level JSON object into a set of key/value pairs. Each row contains one key (key) and its corresponding value (value). Unlike json_each_outer, the value column is of type TEXT, so string values are returned without JSON quotes.

Unlike json_each_text, when the input is NULL or an empty object, json_each_text_outer returns one row of NULL, NULL instead of 0 rows.

Must be used with LATERAL VIEW.

note

Since 4.1.0

Syntax

JSON_EACH_TEXT_OUTER(<json_str>)

Parameters

Parameter	Description
<json_str>	The JSON string to expand. The content must be a JSON object.

Return Value

Returns multi-column, multi-row data. Each row corresponds to one key-value pair in the JSON object:

Column	Type	Description
key	TEXT	The key name from the JSON object
value	TEXT	The corresponding value as plain text (string values have no quotes, e.g. foo)

Special cases:

• If <json_str> is NULL, returns 1 row of NULL, NULL
• If <json_str> is an empty object ({}), returns 1 row of NULL, NULL
• A JSON null value is returned as SQL NULL

Examples

Basic usage: expand a JSON object with string values

SELECT k, v
FROM (SELECT 1) dummy
LATERAL VIEW json_each_text_outer('{"a":"foo","b":"bar"}') t AS k, v;

+---+-----+
| k | v   |
+---+-----+
| a | foo |
| b | bar |
+---+-----+

The value column is of TEXT type, so string values have no JSON quotes (unlike json_each_outer).

NULL parameter: returns 1 row of NULL

SELECT k, v
FROM (SELECT 1) dummy
LATERAL VIEW json_each_text_outer(NULL) t AS k, v;

+------+------+
| k    | v    |
+------+------+
| NULL | NULL |
+------+------+

Empty object: returns 1 row of NULL

SELECT k, v
FROM (SELECT 1) dummy
LATERAL VIEW json_each_text_outer('{}') t AS k, v;

+------+------+
| k    | v    |
+------+------+
| NULL | NULL |
+------+------+