Find derived tables (views and materialized views) that contain more than one DISTINCT invocation. Make sure that the query is correctly written, including that it does not have unwanted formation of a Cartesian product.
Notes
In the returned subquery of view/materialized view 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
General (Overview of some aspect of the database.)
SELECT
table_schema,
table_name,
type,
regexp_replace(view_definition,'[\r\n]',' ','g') AS view_definition
FROM (SELECT
views.table_schema,
views.table_name,
'VIEW' AS type,
views.view_definition
FROM
information_schema.views
WHERE table_schema NOT IN (SELECT schema_name
FROM INFORMATION_SCHEMA.schemata
WHERE schema_name<>'public' AND
schema_owner='postgres' AND schema_name IS NOT NULL)
UNION SELECT schemaname, matviewname, 'MATERIALIZED VIEW' AS type, regexp_replace(definition,'[\r\n]',' ','g') AS definition
FROM pg_catalog.pg_matviews) AS foo
WHERE view_definition ~*'[[:space:]]distinct[[:space:]].+[[:space:]]distinct[[:space:]]'
ORDER BY table_schema, table_name;
Collections
This query belongs to the following collections:
Name
Description
Find problems by overview
Queries 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 .
Categories
This query is classified under the following categories:
Name
Description
Derived tables
Queries of this category provide information about the derived tables (views, materialized views), which are used to implement virtual data layer.