Inconsistent use of gratuitous context in the names of non-foreign key and non-primary key columns

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WITH primary_key_columns AS (select target_schema as table_schema, target_table as table_name, a.attname as column_name
from (select 
(select nspname from pg_namespace where oid=c.relnamespace) as target_schema,
c.relname as target_table, 
c.oid as target_table_oid,
unnest(o.conkey) AS target_col
from pg_constraint o inner join pg_class c on c.oid = o.conrelid
where o.contype in ('p')) t
inner join pg_attribute a on t.target_col = a.attnum and t.target_table_oid = a.attrelid and a.attisdropped = false),
fk_columns AS (
select target_schema as table_schema, target_table as table_name, a.attname as column_name
from (select 
(select nspname from pg_namespace where oid=c.relnamespace) as target_schema,
c.relname as target_table, 
c.oid as target_table_oid,
unnest(o.conkey) AS target_col
from pg_constraint o inner join pg_class c on c.oid = o.conrelid
where o.contype = 'f') t
inner join pg_attribute a on t.target_col = a.attnum and t.target_table_oid = a.attrelid and a.attisdropped = false
),
columns AS (SELECT table_schema, table_name, column_name 
FROM INFORMATION_SCHEMA.columns AS c
WHERE (table_schema, table_name) IN (SELECT table_schema, table_name
FROM INFORMATION_SCHEMA.tables WHERE table_type='BASE TABLE') AND 
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
NOT EXISTS (SELECT 1 FROM primary_key_columns AS pk WHERE pk.table_schema=c.table_schema AND pk.table_name=c.table_name AND pk.column_name=c.column_name) AND
NOT EXISTS (SELECT 1 FROM fk_columns AS fk WHERE fk.table_schema=c.table_schema AND fk.table_name=c.table_name AND fk.column_name=c.column_name)),
stats AS (
SELECT Count(*) FILTER (WHERE column_name ~*  ('^' || table_name || '.{0,1}_')) AS nr_of_columns_that_start_table_name ,
string_agg(table_schema || '.' || table_name || '.' || column_name, ';<br>' ORDER BY table_name, column_name)  FILTER (WHERE column_name ~*  (table_name || '.{0,1}_')) AS columns_that_start_table_name,
Count(*) FILTER (WHERE column_name !~*  ('^' || table_name || '.{0,1}_')) AS nr_of_columns_that_do_not_start_table_name
FROM columns)
SELECT *
FROM stats
WHERE EXISTS (SELECT * FROM columns WHERE column_name ~*  ('^' || table_name || '.{0,1}_'))
AND EXISTS (SELECT * FROM columns WHERE column_name !~*  ('^' || table_name || '.{0,1}_'));