The list of all the queries

Referential degree of tables

Query goal: This metric represents the number of foreign keys in a base table.
Notes about the query: The query returns information about all the base tables, even those that do not have foreign key constraints. In the latter case the number would be 0.
Query type: Sofware measure (Numeric values (software measures) about the database)
Query license: MIT License
Data source: INFORMATION_SCHEMA only
SQL query: Click on query to copy it

SELECT A.table_schema, A.table_name, Count(B.table_name) AS number_of_foreign_keys 
FROM information_schema.tables A
LEFT JOIN 
(SELECT table_schema, table_name
FROM information_schema.table_constraints 
WHERE constraint_type = 'FOREIGN KEY'
) B USING (table_schema, table_name)
INNER JOIN information_schema.schemata C
ON A.table_schema=C.schema_name
WHERE A.table_type='BASE TABLE'
AND (A.table_schema = 'public' OR C.schema_owner<>'postgres')
GROUP BY A.table_schema, A.table_name
ORDER BY Count(B.table_name)  DESC, A.table_schema, A.table_name;

Collections where the query belongs to

Collection nameCollection description
Find problems by overviewQueries that results point to different aspects of database that might have problems. A human reviewer has to decide based on the results as to whether there are problems or not .
Find quick numeric overview of the databaseQueries that return numeric values showing mostly the number of different types of database objects in the database

Categories where the query belongs to

Category nameCategory description
Comfortability of database evolutionQueries of this category provide information about the means that influence database evolution.
Relationships between tablesQueries of this category provide information about how database tables are connected to each other and whether such connections have been explicitly defined and whether it has been done correctly.

Reference materials for further reading

Reference
Piattini, M., Calero, C., Sahraoui, H. A., & Lounis, H. (2001). Object-relational database metrics. L'Objet, 7(4), 477-496.

The list of all the queries