Postgres No Primary Key Drawback [closed]
Solution 1:
Per the Postgres documentation (http://www.postgresql.org/docs/9.2/static/sql-createtable.html):
Technically, PRIMARY KEY is merely a combination of UNIQUE and NOT NULL, but identifying a set of columns as primary key also provides metadata about the design of the schema, as a primary key implies that other tables can rely on this set of columns as a unique identifier for rows.
From my experience, I have created plenty of tables without them. But some replication solutions require there be a primary key, or at the single column identifier per row.