Question

How to find the number of tables present in the databases?

Answer 1

In many ANSI-compliant database systems, you can use catalog table INFORMATION_SCHEMA.TABLES to see list of tables and count them.

This applies to at least following: Oracle, Microsoft, PostgreSQL, MySQL.

Exact numer of tables may surprise you since this can include system tables. You may filter by schema to fix it.

Example (public is default schema in PostgreSQL):

SELECT count(*) AS totalTables 
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'public';