Why is a table showing up twice in pg_class?

Question

I am attempting to run a PostgreSQL statement to query approximate table size count estimate using the following statement:

SELECT reltuples as approximate_row_count FROM pg_class WHERE relname = 'table_name';

ref: Count estimate (PostgreSQL | Wiki)

However, my query is returning two rows, one with a size and one with zero. Why?

Answer 1

Turns out I had the same table (same name) within two different schemas. So each had an entry in pg_class.

Work around from the wiki page is SELECT * FROM pg_class WHERE oid = 'schema_name.table_name'::regclass;