连接数据库服务器，切换至postgres(或其他数据库用户)下，

psql--进入数据库命令行终端，执行如下相关查询操作：

显示数据库：

\l

连接指定的数据库：

\c 数据库名

查看当前实例下的表：

\dt

用sql语句方式查询：

SELECT tablename FROM pg_tables;

查询某张表的表结构及字段信息

\d tablename--实际表名

用sql语句方式查询：

SELECT a.attnum, a.attname AS field, t.typname AS type, a.attlen AS length, a.atttypmod AS lengthvar

, a.attnotnull AS notnull, b.description AS comment

FROM pg_class c, pg_attribute a

LEFT JOIN pg_description b

ON a.attrelid = b.objoid

AND a.attnum = b.objsubid, pg_type t

WHERE c.relname = '实际的表名'

AND a.attnum > 0

AND a.attrelid = c.oid

AND a.atttypid = t.oid

ORDER BY a.attnum;