postgresql表结构查询sql

SELECT
	t1.attnum as "序号",
	t1.attname as "字段名",
	concat_ws ( '', t2.typname, SUBSTRING ( format_type ( t1.atttypid, t1.atttypmod ) FROM '\(.*\)' ) ) AS "数据类型" ,
	t3.description AS "注释" 
	-- (case t1.attnotnull WHEN 'f' THEN '否' ELSE '是' end )AS "必填",
	-- t1.attnotnull as "不是null"
FROM
	pg_attribute t1
	LEFT JOIN pg_type t2 ON t1.atttypid = t2.oid
	LEFT JOIN pg_description t3 ON t3.objoid = t1.attrelid  AND t3.objsubid = t1.attnum 
	LEFT JOIN pg_class t4 ON t1.attrelid = t4.oid
WHERE
	t1.attnum > 0 
	AND t4.relname = 'order'; -- 数据库名称