postgresql 查询表结构

SELECT 
 A.attnum,
    ( SELECT description FROM pg_catalog.pg_description WHERE objoid = A.attrelid AND objsubid = A.attnum ) AS descript,
    A.attname,
    ( select typname from pg_type where oid = A.atttypid) AS type,
    A.atttypmod AS data_type 
FROM
    pg_catalog.pg_attribute A
WHERE
    1 = 1 
    AND A.attrelid = ( SELECT oid FROM pg_class WHERE relname = '表名' ) 
    AND A.attnum > 0 
    AND NOT A.attisdropped 
ORDER BY
    A.attnum;