BigQuery REST API - Unable to use functions - google-bigquery

Question

I'm trying to use the BigQuery REST API to execute some queries, but, for some reason, I can't use SQL functions.
The endpoint I've been using is the following:
POST https://bigquery.googleapis.com/bigquery/v2/projects/{project-id}/queries
This works for regular queries (with no functions), but if I try to use the EXTRACT or FORMAT_DATE functions I always get a 400 Bad Request.
Examples
Payload:
{
"query": "SELECT user_id, timestamp, (EXTRACT(ISOWEEK FROM timestamp)) as week FROM table_name WHERE DATE(_PARTITIONTIME) >= '2022-01-01' ORDER BY week DESC"
}
Response:
{
"error": {
"code": 400,
"message": "Encountered \" \"FROM\" \"FROM \"\" at line 1, column 45.\nWas expecting:\n \")\" ...\n[Try using standard SQL (https://cloud.google.com/bigquery/docs/reference/standard-sql/enabling-standard-sql)]",
"errors": [
{
"message": "Encountered \" \"FROM\" \"FROM \"\" at line 1, column 45.\nWas expecting:\n \")\" ...\n[Try using standard SQL (https://cloud.google.com/bigquery/docs/reference/standard-sql/enabling-standard-sql)]",
"domain": "global",
"reason": "invalidQuery",
"location": "q",
"locationType": "parameter"
}
],
"status": "INVALID_ARGUMENT"
}
}
Second Payload:
{
"query": "SELECT user_id, timestamp, FORMAT_DATE('%Y%W',timestamp) as week FROM table_name WHERE DATE(_PARTITIONTIME) >= '2022-01-01' ORDER BY week DESC"
}
Response:
{
"error": {
"code": 400,
"message": "1.39 - 1.56: Unrecognized function format_date\n[Try using standard SQL (https://cloud.google.com/bigquery/docs/reference/standard-sql/enabling-standard-sql)]",
"errors": [
{
"message": "1.39 - 1.56: Unrecognized function format_date\n[Try using standard SQL (https://cloud.google.com/bigquery/docs/reference/standard-sql/enabling-standard-sql)]",
"domain": "global",
"reason": "invalidQuery",
"location": "q",
"locationType": "parameter"
}
],
"status": "INVALID_ARGUMENT"
}
}
Is there any particular way to escape BigQuery functions in the REST API?
Thank you,

Answer 1

I suspect (give that you mention the REST endpoint directly) you're constructing requests without the use of a client library.
Try setting the "useLegacySQL" field to false as part of the request:
https://cloud.google.com/bigquery/docs/reference/rest/v2/jobs/query#QueryRequest
Due to historical precedent and to avoid breaking users during the evolution of the standard SQL dialect, the default value of this is field is true. The various BigQuery client libraries tend to handle this automatically for you.