jsonextractindex

This section contains reference documentation for the JSONEXTRACTINDEX function.

Evaluates the 'jsonPath' on jsonField, returns the result as the type 'resultsType', use optional defaultValuefor null or parsing error.

The function closely mirrors JSONEXTRACTSCALAR, however, since it extracts values from a JSON Index, it allows for additional filtering to be pushed down.

Compared to JSONEXTRACTSCALAR, this is most useful when extraction is required on a large number of docs, or on large docs. When filtering is highly specific, the original JSONEXTRACTSCALAR implementation is usually faster. For a simple comparsion, see the initial PR #11739

Signature

JSONEXTRACTINDEX(jsonField, 'jsonPath', 'resultsType', [defaultValue], [filter])

Arguments	Description
jsonField	An Identifier/Expression contains JSON documents.
'jsonPath'	Follows JsonPath Syntax to read values from JSON documents.
'resultsType'	One of the Pinot supported data types:INT, LONG, FLOAT, DOUBLE, BOOLEAN, TIMESTAMP, STRING, INT_ARRAY, LONG_ARRAY, FLOAT_ARRAY, DOUBLE_ARRAY, STRING_ARRAY.
'filter'	Pushes down a filter to avoid extracting values that do not match, e.g. "$.arrField[*].f2" > 2.

'jsonPath'and`` ``'resultsType'are literals. Pinot uses single quotes to distinguish them from identifiers.

Usage Examples

The examples in this section are based on the Batch JSON Quick Start. In particular we'll be querying the row WHERE id = 7044874109:

SELECT repo
from githubEvents 
WHERE id = 7044874109

repo
{"id":115911530,"name":"LimeVista/Tapes","url":"https://api.github.com/repos/LimeVista/Tapes"}

The following examples show how to use the JSONEXTRACTINDEX function:

SELECT id, jsonextractindex(repo, '$.name', 'STRING') AS name
FROM githubEvents 
WHERE id = 7044874109

id	name
7044874109	LimeVista/Tapes

SELECT id, jsonextractindex(repo, '$.foo', 'STRING', 'dummyValue') AS name
FROM githubEvents 
WHERE id = 7044874109

id	name
7044874109	dummyValue

SELECT id, jsonextractindex(repo, '$.name', 'STRING', 'dummyValue', '"$.id" < 10') AS name
FROM githubEvents 
WHERE id = 7044874109

id	name
7044874109	LimeVista/Tapes

Array Extraction

The below examples will use the shown arrayField

SELECT repo
FROM myTable 
WHERE id = 123

repo
{"id":"xyz"","arrayField": [{"f1": 1, "f2": 2}, {"f1": 3, "f2": 4}, {"f2": 6}, {"f1": 0, "f2": 5}]}

Extract array values as MV

SELECT id, jsonextractindex(repo, '$.arrayField[*].f1', 'STRING', '[]') AS arrayValues
FROM myTable 
WHERE id = 123

id	arrayValues
123	[1, 3, 0]

Filtering is also allowed on array values:

SELECT id, jsonextractindex(repo, '$.arrayField[*].f1', 'STRING', '[]', '"$.arrField[*].f2" > 2') AS arrayValues
FROM myTable 
WHERE id = 123

id	arrayValues
123	[3, 0]

SELECT id, jsonextractindex(repo, '$.arrayField[*].f1', 'STRING', '[]', '"$.arrField[*].nonExistant" > 99999') AS arrayValues
FROM myTable 
WHERE id = 123

id	arrayValues
123	[]