Postgres: To get list of all partitions of a table

 SELECT

    child.relname AS partition_name

FROM

    pg_class base_tb

JOIN

    pg_inherits i ON i.inhparent = base_tb.oid

JOIN

    pg_class child ON i.inhrelid = child.oid

LEFT JOIN

    pg_partitioned_table pt ON pt.partrelid = child.oid

WHERE

    base_tb.relname = 'coupons';