FOR UPDATE in derived tables

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Goal Find derived tables that subquery uses FOR UPDATE construct. Reading a data element shouldn't block other read operations of the same element. Thus, you shouldn't use exclusive locking command in a view.
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 Problem detection (Each row in the result could represent a flaw in the design)
Reliability High (Few or no false-positive results)
License MIT License
Fixing Suggestion Drop the view and recreate it without using FOR UPDATE in the subquery.
Data Source INFORMATION_SCHEMA+system catalog
SQL Query 
SELECT
table_schema,
table_name,
type,
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:]]+for[[:space:]]+update'
ORDER BY table_schema, table_name;

SQL statements that help generate fixes for the identified problem.

SQL Query to Generate FixDescription
SELECT format('DROP VIEW %1$I.%2$I;', views.table_schema, views.table_name) AS statements
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)
AND view_definition ~*'^.+[[:space:]]+for[[:space:]]+update.*$'
ORDER BY table_schema, table_name;
Drop the view.
SELECT format('DROP MATERIALIZED VIEW %1$I.%2$I;', schemaname, matviewname) AS statements
FROM pg_catalog.pg_matviews
WHERE definition ~*'^.+[[:space:]]+for[[:space:]]+update.*$'
ORDER BY schemaname, matviewname;
Drop the materialized view.
Collections

This query belongs to the following collections:

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:

NameDescription
Concurrency controlQueries of this category provide information about concurrency control.
Derived tablesQueries of this category provide information about the derived tables (views, materialized views), which are used to implement virtual data layer.
PerformanceQueries of this category provide information about indexes in a database.