How many tables are there in a database?
The number of tables in a relational database is a good measure of the complexity of a database, so it is a simple way to get to know any database. But what kind of complexity exactly? Well, a database may be complex because it has been designed to be deliberately flexible, in order to cover a variety of business situations. It could also be that a complex business process may have a limited portion of its details covered in the database. So a large number of tables might reveal a complex business process or just a complex piece of software.
In this recipe, we will show you how to compute the number of tables.
How to do it...
From any interface, type the following SQL command:
SELECT count(*) FROM information_schema.tables
WHERE table_schema NOT IN ('information_schema','pg_catalog');
You can also look at the list of tables directly and judge whether the list is small or large.
In psql, you can see...
