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with fk as (select 
o.conname,
(select nspname from pg_namespace where oid=f.relnamespace) as foreign_schema,
f.relname as foreign_table,
f.oid as foreign_table_oid,
o.confkey AS foreign_col,
(select nspname from pg_namespace where oid=c.relnamespace) as target_schema,
c.relname as target_table, 
c.oid as target_table_oid,
o.conkey AS target_col
from pg_constraint o inner join pg_class c on c.oid = o.conrelid
inner join pg_class f on f.oid = o.confrelid 
where o.contype = 'f'),
fk_unnest as (select conname, foreign_schema, foreign_table,  foreign_table_oid, foreign_col, foreign_col_num, target_schema, target_table, target_table_oid, target_col, target_col_num, ordin
from fk, unnest(fk.foreign_col, fk. target_col) with ordinality as f(foreign_col_num, target_col_num, ordin)),
fk_with_names as (select conname, foreign_schema, foreign_table, a_foreign.attname as foreign_col, target_schema, target_table, a_target.attname as target_col
from fk_unnest fk inner join pg_attribute a_foreign on fk.foreign_col_num = a_foreign.attnum and fk.foreign_table_oid = a_foreign.attrelid and a_foreign.attisdropped = false
inner join pg_attribute a_target on fk.target_col_num = a_target.attnum and fk.target_table_oid = a_target.attrelid and a_target.attisdropped = false),
data_types AS (SELECT table_schema, table_name, column_name, 
CASE WHEN data_type='numeric' THEN data_type || '(' || numeric_precision || ',' || numeric_scale || ')'
WHEN character_maximum_length IS NOT NULL THEN data_type || '(' ||  character_maximum_length || ')'
WHEN datetime_precision IS NOT NULL AND data_type<>'date' THEN data_type || '(' ||  datetime_precision || ')'
ELSE data_type END AS data_type
FROM INFORMATION_SCHEMA.columns
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))
select fk.*, dtf.data_type AS foreign_data_type, dtt.data_type AS target_data_type
from fk_with_names AS fk inner join data_types AS dtf ON fk.foreign_schema=dtf.table_schema AND fk.foreign_table=dtf.table_name AND fk.foreign_col=dtf.column_name
inner join data_types AS dtt ON fk.target_schema=dtt.table_schema AND fk.target_table=dtt.table_name AND fk.target_col=dtt.column_name
WHERE dtt.data_type!~*'(smallint|integer|bigint|character varying[(][[:digit:]]+[)])'
order by target_schema, target_table, conname;