Goal Find table functions that do not have any parameters. Prefer simpler and more portable solutions.
Notes Refers to the column pg_proc.prokind and thus works starting from PostgreSQL 11. In the returned body of routine the query replaces each newline character with the line break (br) tag for the better readability in case the query result is displayed in a web browser.
Type Problem detection (Each row in the result could represent a flaw in the design)
Reliability High (Few or no false-positive results)
License MIT (opens in new tab)
Fixing Suggestion Create a view instead of the non-parameterized table function.
Data Source INFORMATION_SCHEMA+system catalog
SQL Query 
SELECT 
  pg_namespace.nspname AS func_schema, 
  pg_proc.proname AS func_name, 
  regexp_replace(pg_get_functiondef(pg_proc.oid),'[\r\n]','<br>','g')  AS func_src,
  pg_type.typname AS return_type
FROM 
  pg_catalog.pg_proc, 
  pg_catalog.pg_namespace,
  pg_catalog.pg_type
WHERE   pg_proc.pronamespace = pg_namespace.oid 
AND pg_type.oid=pg_proc.prorettype
AND pg_proc.prokind='f'
AND  pg_type.typtype='c' 
AND pg_proc.pronargs=0
AND pg_namespace.nspname NOT IN (SELECT schema_name
FROM INFORMATION_SCHEMA.schemata
WHERE schema_name<>'public' AND
schema_owner='postgres' AND schema_name IS NOT NULL) 
ORDER BY func_schema, func_name;

SQL statements that help generate fixes for the identified problem.

Fix Action #1
SELECT format('DROP FUNCTION %1$I.%2$I;', pg_namespace.nspname, pg_proc.proname) AS statements
FROM 
  pg_catalog.pg_proc, 
  pg_catalog.pg_namespace,
  pg_catalog.pg_type
WHERE   pg_proc.pronamespace = pg_namespace.oid AND pg_type.oid=pg_proc.prorettype
AND pg_proc.prokind='f'
AND  pg_type.typtype='c' 
AND pg_proc.pronargs=0
AND pg_namespace.nspname NOT IN (SELECT schema_name
FROM INFORMATION_SCHEMA.schemata
WHERE schema_name<>'public' AND
schema_owner='postgres' AND schema_name IS NOT NULL) 
ORDER BY pg_namespace.nspname, pg_proc.proname;

Drop the function.

SQL Query to Generate FixDescription
SELECT format('DROP FUNCTION %1$I.%2$I;', pg_namespace.nspname, pg_proc.proname) AS statements
FROM 
  pg_catalog.pg_proc, 
  pg_catalog.pg_namespace,
  pg_catalog.pg_type
WHERE   pg_proc.pronamespace = pg_namespace.oid AND pg_type.oid=pg_proc.prorettype
AND pg_proc.prokind='f'
AND  pg_type.typtype='c' 
AND pg_proc.pronargs=0
AND pg_namespace.nspname NOT IN (SELECT schema_name
FROM INFORMATION_SCHEMA.schemata
WHERE schema_name<>'public' AND
schema_owner='postgres' AND schema_name IS NOT NULL) 
ORDER BY pg_namespace.nspname, pg_proc.proname;
Drop the function.

Collections

This query belongs to the following collections:

Find problems automatically

Queries, that results point to problems in the database. Each query in the collection produces an initial assessment. However, a human reviewer has the final say as to whether there is a problem or not .

NameDescription
Find problems automaticallyQueries, that results point to problems in the database. Each query in the collection produces an initial assessment. However, a human reviewer has the final say as to whether there is a problem or not .

Categories

This query is classified under the following categories:

Derived tables

Queries of this category provide information about the derived tables (views, materialized views), which are used to implement virtual data layer.

Does not work in some earlier PostgreSQL version

Queries of this category provide information that was not available in some earlier PostgreSQL version

User-defined routines

Queries of this category provide information about the user-defined routines

NameDescription
Derived tablesQueries of this category provide information about the derived tables (views, materialized views), which are used to implement virtual data layer.
Does not work in some earlier PostgreSQL versionQueries of this category provide information that was not available in some earlier PostgreSQL version
User-defined routinesQueries of this category provide information about the user-defined routines