First, we will show you how to identify columns that are defined in different ways in different tables, using a query against the catalog. We use an information_schema query, as follows:
SELECT table_schema,table_name,column_name,data_type ||coalesce(' ' || text(character_maximum_length), '') ||coalesce(' ' || text(numeric_precision), '') ||coalesce(',' || text(numeric_scale), '') as data_typeFROM information_schema.columnsWHERE column_name IN(SELECT column_nameFROM(SELECT column_name ,data_type ,character_maximum_length ,numeric_precision ,numeric_scale FROM information_schema.columns WHERE table_schema NOT IN ('information_schema', 'pg_catalog') GROUP BY column_name ,data_type ,character_maximum_length ,numeric_precision ...
