The query below lists the tables that are most referenced by other tables with foreign keys. Those are the dictionary tables such as person, product or store. In data warehouses those are dimension tables.
select concat(unique_constraint_schema, '.', referenced_table_name) as 'table', count(*) as 'references', count(distinct concat(constraint_schema, '.', table_name)) as referencing_tables from information_schema.referential_constraints -- where constraint_schema = 'database name' -- provide database name here group by unique_constraint_schema, referenced_table_name order by 2 desc, referencing_tables desc;
- table - name of the table
- references - number of foreign keys referencing to this table
- referencing_tables - number of different tables referencing to this table
- One row: represents one table in a database (schema)
- Scope of rows: tables being used in foreign keys as primary key table
- Ordered by: number of references in descending order and number of referencing tables in descending order
List of most referenced tables in sakila database. Staff table is referenced 3 times from 3 different tables.