Postgresql system tables have OIDs instead of table IDs, but the use of OIDs is deprecated, so use sequential numbers instead.
[System]Get TableName
SELECT "tablename","schemaname" FROM "pg_tables"
[System]Get FieldName and FieldType
SELECT "ordinal_position","column_name","data_type"
FROM information_schema.columns
WHERE table_schema ='<Schema Name>' AND table_name= '<Table Name>'
ORDER BY ordinal_position