How to get query results from TableResult in json using BigQuery API - google-bigquery

Question

I'm following the example given in https://cloud.google.com/bigquery/create-simple-app-api#bigquery-simple-app-java to obtain query results from BigQuery API.
TableResult result = queryJob.getQueryResults();
It returns the results in a TableResults type but I need to get the results in a json format.
TableResult{rows=[[FieldValue{attribute=PRIMITIVE, value=(...)},
FieldValue{attribute=PRIMITIVE, value=(...)},
FieldValue{attribute=PRIMITIVE, value=(...)},
FieldValue{attribute=PRIMITIVE, value=(...)},
FieldValue{attribute=PRIMITIVE, value=(...)},
FieldValue{attribute=PRIMITIVE, value=(...)},
FieldValue{attribute=PRIMITIVE, value=(...)}],(...)
How can I transform the results in TableResults type to json, or even csv?

Answer 1

To convert rows in a table to JSON you can use the function TO_JSON_STRING [1].
To get a JSON with formatting you need to pass the parameter “true” to the function.
The new query would look like this:
#standardSQL
“SELECT TO_JSON_STRING(t,true)"
+ "FROM (
SELECT CONCAT('https://stackoverflow.com/questions/', CAST(id as STRING)) as url, "
+ "view_count "
+ "FROM `bigquery-public-data.stackoverflow.posts_questions` "
+ "WHERE tags like '%google-bigquery%' "
+ "ORDER BY favorite_count DESC LIMIT 10) as t”
Output:
TableResult{rows=[[FieldValue{attribute=PRIMITIVE, value={
"url": "https://stackoverflow.com/questions/6607552",
"view_count": 24524
}}], [FieldValue{attribute=PRIMITIVE, value={
"url": "https://stackoverflow.com/questions/20349189",
"view_count": 4298
}}], [FieldValue{attribute=PRIMITIVE, value={
"url": "https://stackoverflow.com/questions/22734777",
"view_count": 7940
}}], [FieldValue{attribute=PRIMITIVE, value={
"url": "https://stackoverflow.com/questions/27537720",
"view_count": 2039
(...)