invalid input syntax for type json" source="postgres_exporter.go:1356"

[kumarvijendar]

I am trying to use postgres-operator version 4.6.1/4.6.2 with posgtres version 12.6 i'e crunchy-postgres-ha:centos8-12.6-4.6.1 and centos8-12.6-4.6.2.
In both of the versions, when I deploy the cluster and try to check the exporters logs, I get following error.

time="2021-04-19T09:04:59Z" level=error msg="queryNamespaceMappings returned 4 errors" source="postgres_exporter.go:1474"
time="2021-04-19T09:05:59Z" level=info msg="Error running query on database \"127.0.0.1:5432\": ccp_backrest_last_diff_backup pq: invalid input syntax for type json" source="postgres_exporter.go:1356"
time="2021-04-19T09:07:00Z" level=info msg="Error running query on database \"127.0.0.1:5432\": ccp_backrest_last_incr_backup pq: invalid input syntax for type json" source="postgres_exporter.go:1356"
time="2021-04-19T09:08:00Z" level=info msg="Error running query on database \"127.0.0.1:5432\": ccp_backrest_last_diff_backup pq: invalid input syntax for type json" source="postgres_exporter.go:1356"
time="2021-04-19T09:09:00Z" level=info msg="Error running query on database \"127.0.0.1:5432\": ccp_backrest_last_incr_backup pq: invalid input syntax for type json" source="postgres_exporter.go:1356"
time="2021-04-19T09:10:01Z" level=info msg="Error running query on database \"127.0.0.1:5432\": ccp_backrest_last_info pq: invalid input syntax for type json" source="postgres_exporter.go:1356"
time="2021-04-19T09:11:01Z" level=info msg="Error running query on database \"127.0.0.1:5432\": ccp_backrest_last_full_backup pq: invalid input syntax for type json" source="postgres_exporter.go:1356"
time="2021-04-19T09:12:02Z" level=info msg="Error running query on database \"127.0.0.1:5432\": ccp_backrest_last_info pq: invalid input syntax for type json" source="postgres_exporter.go:1356"
time="2021-04-19T09:13:02Z" level=info msg="Error running query on database \"127.0.0.1:5432\": ccp_backrest_last_diff_backup pq: invalid input syntax for type json" source="postgres_exporter.go:1356"